Bucket Brigade, Fire Engine, Sprinkler System, Sprinkler Head, Fire Pump, Jockey Pump, Wet-Pipe and Dry-Pipe

Posted by PITHOCRATES - April 23rd, 2014

Technology 101

(Originally published March 20th, 2013)

A Fire Engine can move Water Faster and Farther with an Internal Combustion Engine than with a Steam Engine

Some of our earliest firefighters were bucket brigades.  Where people would form lines between a fire and a water source.  Someone would dip a bucket into the water source.  And then pass it to the next person in line.  Who would then pass it to the next person in line.  And so on until the bucket reached the person at the other end of the line.  Who then poured the water on the fire.  Then the empty buckets would work their way the other way back towards the water source.  Buckets of water moved from the source of water to the fire.  While empty buckets moved from the fire to the water source.

This was state of the art firefighting at the time.  As long as there were enough people to form a line from the water source to the fire.  The people didn’t tire out before the fire did.  And the fire wasn’t so large that buckets of water couldn’t put it out.  But soon we developed the hand-operated pump on our first fire engines.  And the fire hose.  Then we just had to run a fire hose from the water source to the fire engine.  And a fire hose from the fire engine to the fire.  People could take turns hand pumping, producing a steady stream of water.  That someone could direct onto a fire.  These new firefighting crews could put out large fires in shorter times.  Fire companies appeared in cities with trained firefighters.  Providing safer cities.  A great improvement over the bucket brigade.  But not as good as what came next.

Men pulled the early fire engines.  Then horses replaced men.  But the big advancement was in the fire pump.  When steam power replaced hand power.  Allowing greater flows of water at higher pressures.  Allowing firefighters to attack a fire from a safer distance.  But steam had some drawbacks.  It took time to boil water into steam.  Steam engines needed boiler operators to carefully operate the boiler so it didn’t explode.  And being an external combustion engine there were a lot of moving parts in the open.  That could be dangerous to the firefighters.  And being exposed to the elements they needed constant oiling.  The internal combustion engine didn’t suffer any of these drawbacks.  The modern fire engine is safer.  Easier to operate.  More efficient.  And can move more water faster and farther.

A Jockey Pump in a Sprinkler System maintains the Water Pressure when there’s no Fire

But even the modern fire engine has one drawback.  We park them at firehouses.  While all our fires are not at firehouses.  So they have to drive to the fire.  Which they can do pretty quickly.  But that’s still time a fire can grow.  Causing more damage.  Become stronger.   And more difficult to put out.  Which is why we brought fire-fighting water into buildings.  To use on a fire even before the fire department arrives on the scene.  Buildings today have fire sprinkler systems.  Pipes filled with water covering every square inch of a building.  That will release their water through the various sprinkler heads attached to these pipes.

The sprinkler head is a marvel of low-tech.  It is basically a threaded fitting that screws into the water-filled pipe.  The sprinkler head has a hole in it.  A glass bulb with a liquid inside of it holds a plug in the hole.  Preventing the flow of water.  If there is a fire under this head the heat will cause the liquid in the glass bulb to expand.  Eventually shattering the glass bulb.  The water pressure inside the pipe will blow out the plug.  Allowing the water to flow out of the pipe.  As it does it hits a deflector, producing a spray pattern that will evenly cover the area underneath the head.  Only areas where there is a fire will break these glass bulbs.  So only the sprinklers over fires will discharge their water.  Preventing water damage in areas where there is no fire.

Some buildings can operate off of city water pressure.  But larger buildings, especially multistory buildings, need help to maintain the water pressure in the system.  These buildings have fire pumps.  A large pump that can maintain the pressure in the sprinkler lines even if all the sprinkler heads are discharging water.  And a smaller jockey pump.  Which maintains the pressure in the system when there is no fire.  If the pressure drops below a lower limit the jockey pump comes on.  When the pressure rises above a higher limit the jockey pump shuts down.  If there is a fire in the building the fire pump will run until it melts down.  Putting water on the fire as long as it can.

A Dry-Pipe Fire Sprinkler System in an Unheated Area is often attached to a Wet-Pipe System in a Heated Area

If water would greatly damage an area (such as a hardwood basketball court) they may add a valve on the pipe feeding the sprinkler piping over the floor.  Keeping the water out of the pipes over the expensive hardwood floor.  Smoke detectors in the ceiling will open the valve when they detect a fire.  Letting water flow into the sprinkler lines over the floor.  And out of any sprinkler head over a fire hot enough to have broken the glass bulb to release the plug.

Water damage is a real concern.  For it may be a better alternative to fire damage.  But water damage in absence of any fire can be costly.  Something many have seen working on a new building in a northern climate.  During the first freeze.   If there was missed insulation on an exterior wall.  Under-designed heating in an exterior glass-enclosed stairwell.  Or both in a glass-enclosed vestibule that juts outside of a heated building.  As temperatures fall cold air migrates around these sprinkler lines.  Freezing the water inside.  Causing them to burst.  And when they do it releases the water pressure behind these frozen sections.  Flooding these areas with water.  Causing a lot of damage.  Not to mention the damage to the fire sprinkler system.

Some unheated areas need a sprinkler system.  But these pipes can’t be a wet-pipe system.  Because if there was water in the pipes it would freeze.  Breaking the pipes.  So we use a dry-pipe system in unheated areas.  Which is often attached a wet-pipe system.  Such as a dry-pipe system in an exterior canopy attached to a heated building.  There is a valve between the interior wet-pipe system and the exterior dry-pipe system.  An air compressor will put air under pressure in the dry-pipe system.  This air pressure will hold the valve close to the wet-pipe system.  If there is a fire underneath the canopy the glass bulb in a sprinkler head will expand and break.  Releasing the air from the dry-pipe system.  Allowing the water pressure in the wet-pipe system to open the valve.  Flooding the dry-pipe system.  And flowing out of the sprinkler head over the fire.

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The EPA is Poisoning People while Fracking is making People’s lives Better

Posted by PITHOCRATES - April 5th, 2014

Week in Review

There have been a lot of movies showing how fracking is polluting our groundwater.  Giving people cancer.  Causing fire to blow out of people’s water faucets.  Makers of movies appear on The Daily Show and The Colbert Report talking about how horrible and dangerous fracking is.  So the evils of fracking are all around us.  But, strangely, these dangers are conspicuous by their absence in one area.  Actual news stories.

We hear about how global warming is getting worse.  We hear example after example of how Republicans hate the poor and women and want to take away health insurance from everyone.  We are bombarded with news about how the rich aren’t paying their fair share and how Republicans are trying to buy elections.  But we don’t see reporters filming fire shooting out of a water faucet.  And we don’t see the CDC in fracking areas responding to soaring cancer rates.  Or fracking fields being turned into superfund cleanup sites.

It’s odd because when Malaysian Airways Flight 370 went missing 4 weeks ago CNN covered the missing airplane 24/7.  Even though they had nothing to report.  They just brought in experts (and a physic) and theorized about what might have happened.  The other news channels covered the non-news with nearly the same fervor as CNN.  So you would think that if fracking was causing fire to shoot out of water faucets and was giving everyone cancer they would be covering that 24/7.  For most of these news channels are liberal.  And liberals hate fracking.  But they don’t go to North Dakota to report the abject misery fracking has brought them.  Probably because they don’t want to show the economic boom going on in North Dakota.  Where people are going to for jobs.  Where the unemployment rate there (2.6% as of February 2014) is the lowest in the nation.  Perhaps that’s why they don’t report the abject misery fracking is causing in North Dakota.  Because there is none.

So if the media isn’t in North Dakota is the government?  Is the EPA documenting the abject misery fracking is causing the good people of North Dakota?  No.  Instead, they’re purposely trying to give people cancer (see What’s more dangerous to your health than fracking? The EPA, apparently by Ashe Schow posted 4/2/2014 on the Washington Examiner).

An EPA inspector general’s report found that the agency did obtain approval to conduct five “human research studies” exposing “81 human study subjects to” toxic pollutants including diesel exhaust…

So the EPA asked people to expose themselves to dangerous pollutants — some at levels 50 times greater than what is safe — but didn’t tell them about the dangers.

Why would the EPA, which supposedly cares so much about the public’s health, do this, especially to people who already had health problems?

To justify more regulations and funding, of course.

They are desperately trying to kill people by exposing them to something they can later call a toxic pollutant.  So they can “justify more regulations and funding.”  And they will tell the people they kill, “Fear not, you shall not have died in vain.  Your horrible death will bring about the greatest kind of good there is.  It will enable us to expand the size of the federal government.  Allowing it to reach further into your lives.  Well, not yours per se because you’ll be dead.  Thanks to us.  But other people will know the joy of having the federal government intruding further into their private lives.  Until one day there are no more private lives.”

This is what the federal government thinks is good.  Not a 2.6% unemployment rate.  Like they have in North Dakota.  Thanks to fracking.  Which the people living there don’t seem to mind.  As the people moving there don’t seem to mind.  Interestingly, the blue states with higher concentrations of liberals aren’t enjoying such economic prosperity.   The unemployment rate in New York is 6.8%.  In Illinois it’s 8.7%.  And in California it’s 8%.  So they’re doing something right in North Dakota.  And something very wrong in New York, Illinois and California.  Perhaps committing too many resources on liberal policies.  Instead of creating an economic climate that will give people the thing they want most.  A job.

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On the Flightdeck during Aviation Disasters

Posted by PITHOCRATES - March 19th, 2014

Technology 101

USAir Flight 427 on Approach to Pittsburgh flew through Wake Vortex and Lost Control

Malaysian Airlines Flight 370 search is still ongoing.  We’re seemingly no closer to understanding what happened than before.  There has been a lot of speculation.  And rebuttals to that speculation.  With many people saying things like why didn’t the crew radio?  Why didn’t they report a problem?  While others are saying that it is proof for their speculative theory.  That they were either under duress, had no time or were in on it and, therefore, went silent.  So what is it like on the flightdeck when something happens to an aircraft?  Well, because of past CVR (cockpit voice recorder) transcripts from previous accidents, we can get an idea.

On September 8, 1994, USAir Flight 427 flew into the wake vortex (little tornados trailing from a large plane’s wingtip) of a Delta Airlines Boeing 727 ahead of it.  This sideways tornado disrupted the airflow over the control surfaces of the USAir 737.  Disrupting it from level flight, causing it to roll left.  The autopilot tried to correct the roll as the 737 passed through the wake vortex core.  Causing more disruption of the airflow over the control surfaces.  The first officer then tried to stabilize the plane.  Control of the aircraft continued to deteriorate.  We pick up the CVR transcript just before this event (see 8 September 1994 – USAir 427).  CAUTION: The following recounts the final moments of Flight 427 and some may find it disturbing.

CAM-1 = Captain
CAM-2 = First Officer
CAM-3 = Cockpit Area Mike (cabin sounds and flight attendants)
RDO-1 = Radio Communications (Captain)
APP: Pittsburgh Approach

APP: USAir 427, turn left heading one zero zero. Traffic will be one to two o’clock, six miles, northbound Jetstream climbing out of thirty-three for five thousand.
RDO-1: We’re looking for the traffic, turning to one zero zero, USAir 427.
CAM-3: [Sound in engines increasing rpms]
CAM-2: Oh, yeah. I see the Jetstream.
CAM-1: Sheez…
CAM-2: zuh?
CAM-3: [Sound of thump; sound like ‘clickety-click’; again the thumping sound, but quieter than before]
CAM-1: Whoa … hang on.
CAM-3: [Sound of increasing rpms in engines; sound of clickety-click; sound of trim wheel turning at autopilot trim speed; sound similar to pilot grunting; sound of wailing horn similar to autopilot disconnect warning]
CAM-1: Hang on.
CAM-2: Oh, Shit.
CAM-1: Hang on. What the hell is this?
CAM-3: [Sound of stick shaker; sound of altitude alert]
CAM-3: Traffic. Traffic.
CAM-1: What the…
CAM-2: Oh…
CAM-1: Oh God, Oh God…
APP: USAir…
RDO-1: 427, emergency!
CAM-2: [Sound of scream]
CAM-1: Pull…
CAM-2: Oh…
CAM-1: Pull… pull…
CAM-2: God…
CAM-1: [Sound of screaming]
CAM-2: No… END OF TAPE.

At 19:03:01 in the flight there was a full left rudder deflection.  The plane yawed (twisted like a weathervane) to the left.  A second later it rolled 30 degrees left.  This caused the aircraft to pitch down.  Where it continued to roll.  The plane rolled upside down and pitched further nose-down.  The pilots never recovered.  The plane flew nearly straight into the ground at 261kts.  The crash investigated focused on the rudder.  Boeing redesigned it.  Pilots since have received more training on rudder inputs.  And flight data recorders now record additional rudder data.  This incident shows how fast a plane can go from normal flight to a crash.  The captain had time to radio one warning.  But within seconds from the beginning of the event the plane crashed.  Illustrating how little time pilots have to identify problems and correct them.

An In-Flight Deployment of a Thrust Reverser breaks up Lauda Air Flight 004

A plane wants to fly.  It is inherently stable.  As long as enough air flows over its wings.  Jet engines provide thrust that push an airplane’s wings through the air.  The curved surfaces of the wings interacting with the air passing over it creates lift.  As long as a plane’s jet engines push the wing through the air a plane will fly.  On May 26, 1991, something happened to Lauda Air Flight 004 to disrupt the smooth flow of air over the Boeing 767’s wings.  Something that isn’t supposed to happen during flight.  But only when a plane lands.  Reverse thrust.  As a plane lands the pilot reverses the thrust on the jet engines to slow the airplane.  Unfortunately for Flight 004, one of its jet engines deployed its thrust reverser while the plane was at about 31,000 feet.  We pick up the CVR transcript just as they receive a warning indication that the reverse thruster could deploy (see 26 May 1991 – Lauda 004).  CAUTION: The following recounts the final moments of Flight 004 and some may find it disturbing.

23.21:21 – [Warning light indicated]

23.21:21 FO: Shit.

23.21:24 CA: That keeps, that’s come on.

23.22:28 FO: So we passed transition altitude one-zero-one-three

23.22:30 CA: OK.

23.23:57 CA: What’s it say in there about that, just ah…

23.24:00 FO: (reading from quick reference handbook) Additional system failures may cause in-flight deployment. Expect normal reverse operation after landing.

23.24:11 CA: OK.

23.24:12 CA: Just, ah, let’s see.

23.24:36 CA: OK.

23.25:19 FO: Shall I ask the ground staff?

23.25:22 CA: What’s that?

23.25:23 FO: Shall I ask the technical men?

23.25:26 CA: Ah, you can tell ’em it, just it’s, it’s, it’s, just ah, no, ah, it’s probably ah wa… ah moisture or something ’cause it’s not just, oh, it’s coming on and off.

23.25:39 FO: Yeah.

23.25:40 CA: But, ah, you know it’s a … it doesn’t really, it’s just an advisory thing, I don’t ah …

23.25:55 CA: Could be some moisture in there or somethin’.

23.26:03 FO: Think you need a little bit of rudder trim to the left.

23.26:06 CA: What’s that?

23.26:08 FO: You need a little bit of rudder trim to the left.

23.26:10 CA: OK.

23.26:12 CA: OK.

23.26:50 FO: (starts adding up figures in German)

23.30:09 FO: (stops adding figures)

23.30:37 FO: Ah, reverser’s deployed.

23.30:39 – [sound of snap]

23.30:41 CA: Jesus Christ!

23.30:44 – [sound of four caution tones]

23.30:47 – [sound of siren warning starts]

23.30:48 – [sound of siren warning stops]

23.30:52 – [sound of siren warning starts and continues until the recording ends]

23.30:53 CA: Here, wait a minute!

23.30:58 CA: Damn it!

23.31:05 – [sound of bang]

[End of Recording]

The 767 Emergency/Malfunction Checklist stated that upon receiving the warning indicator ADDITIONAL system faults MAY cause an in-flight deployment of the thrust reverser.  But that one warning indication was NOT expected to cause any problem with the thrust reversers in stopping the plane after landing.  At that point it was not an emergency.  So they radioed no emergency.  About 10 minutes later the thrust reverser on the left engine deployed in flight.  When it did the left engine pulled the left wing back as the right engine pushed the right wing forward.  Disrupting the airflow over the left wing.  Causing it to stall.  And the twisting force around the yaw axis created such great stresses on the airframe that the aircraft broke up in the air.  The event happened so fast from thrust reverser deployment to the crash (less than 30 seconds) the crew had no time to radio an emergency before crashing.

Fire in the Cargo Hold brought down ValuJet Flight 592

One of the most dangerous things in aviation is fire.  Fire can fill the plane with smoke.  It can incapacitate the crew.  It can burn through electric wiring.  It can burn through control cables.  And it can burn through structural components.  A plane flying at altitude must land immediately on the detection of fire/smoke.  Because they can’t pull over and get out of the plane.  They have to get the plane on the ground.  And the longer it takes to do that the more damage the fire can do.  On May 11, 1996, ValuJet Flight 592 took off from Miami International Airport.  Shortly into the flight they detected smoke inside the McDonnell Douglas DC-9.  We pick up the CVR transcript just before they detected fire aboard (see 11 May 1996 – ValuJet 591).  CAUTION: The following recounts the final moments of Flight 592 and some may find it disturbing.

CAM — Cockpit area microphone voice or sound source
RDO — Radio transmissions from Critter 592
ALL — Sound source heard on all channels
INT — Transmissions over aircraft interphone system
Tower — Radio transmission from Miami tower or approach
UNK — Radio transmission received from unidentified source
PA — Transmission made over aircraft public address system
-1 — Voice identified as Pilot-in-Command (PIC)
-2 — Voice identified as Co-Pilot
-3 — Voice identified as senior female flight attendant
-? — Voice unidentified
* — Unintelligible word
@ — Non pertinent word
# — Expletive
% — Break in continuity
( ) — Questionable insertion
[ ] — Editorial insertion
… — Pause

14:09:36 PA-2 flight attendants, departure check please.

14:09:44 CAM-1 we’re *** turbulence

14:09:02 CAM [sound of click]

14:10:03 CAM [sound of chirp heard on cockpit area microphone channel with simultaneous beep on public address/interphone channel]

14:10:07 CAM-1 what was that?

14:10:08 CAM-2 I don’t know.

14:10:12 CAM-1 *** (’bout to lose a bus?)

14:10:15 CAM-1 we got some electrical problem.

14:10:17 CAM-2 yeah.

14:10:18 CAM-2 that battery charger’s kickin’ in. ooh, we gotta.

14:10:20 CAM-1 we’re losing everything.

14:10:21 Tower Critter five-nine-two, contact Miami center on one-thirty-two-forty-five, so long.

14:10:22 CAM-1 we need, we need to go back to Miami.

14:10:23 CAM [sounds of shouting from passenger cabin]

14:10:25 CAM-? fire, fire, fire, fire [from female voices in cabin]

14:10:27 CAM-? we’re on fire, we’re on fire. [from male voice]

14:10:28 CAM [sound of tone similar to landing gear warning horn for three seconds]

14:10:29 Tower Critter five-ninety-two contact Miami center, one-thirty-two-forty-five.

14:10:30 CAM-1 ** to Miami.

14:10:32 RDO-2 Uh, five-ninety-two needs immediate return to Miami.

14:10:35 Tower Critter five-ninety-two, uh, roger, turn left heading two-seven-zero.  Descend and maintain seven-thousand.

14:10:36 CAM [sounds of shouting from passenger cabin subsides]

14:10:39 RDO-2 Two-seven-zero, seven-thousand, five-ninety-two.

14:10:41 Tower What kind of problem are you havin’?

14:10:42 CAM [sound of horn]

14:10:44 CAM-1 fire

14:10:46 RDO-2 Uh, smoke in the cockp … smoke in the cabin.

14:10:47 Tower Roger.

14:10:49 CAM-1 what altitude?

14:10:49 CAM-2 seven thousand.

14:10:52 CAM [sound similar to cockpit door moving]

14:10:57 CAM [sound of six chimes similar to cabin service interphone]

14:10:58 CAM-3 OK, we need oxygen, we can’t get oxygen back here.

14:11:00 INT [sound similar to microphone being keyed only on Interphone channel]

14:11:02 CAM-3 *ba*, is there a way we could test them? [sound of clearing her voice]

14:11:07 Tower Critter five-ninety-two, when able to turn left heading two-five-zero.  Descend and maintain five-thousand.

14:11:08 CAM [sound of chimes similar to cabin service interphone]

14:11:10 CAM [sounds of shouting from passenger cabin]

14:11:11 RDO-2 Two-five-zero seven-thousand.

14:11:12 CAM-3 completely on fire.

14:11:14 CAM [sounds of shouting from passenger cabin subsides]

14:11:19 CAM-2 outta nine.

14:11:19 CAM [sound of intermittant horn]

14:11:21 CAM [sound similar to loud rushing air]

14:11:38 CAM-2 Critter five-ninety-two, we need the, uh, closest airport available …

14:11:42 Tower Critter five-ninety-two, they’re going to be standing by for you. You can plan runway one two to dolpin now.

14:11:45 one minute and twelve second interruption in CVR recording]

14:11:46 RDO-? Need radar vectors.

14:11:49 Tower critter five ninety two turn left heading one four zero 14:11:52

RDO-? one four zero

14:12:57 CAM [sound of tone similar to power interruption to CVR]

14:12:57 CAM [sound similar to loud rushing air]

14:12:57 ALL [sound of repeating tones similar to CVR self test signal start and continue]

14:12:58 Tower critter five ninety two contact miami approach on corrections no you you just keep my frequency

14:13:11 CAM [interruption of unknown duration in CVR recording]

14:13:15 CAM [sounds of repeating tones similar to recorder self-test signal starts and continues, rushing air.]

14:13:18 Tower critter five ninety two you can uh turn left heading one zero zero and join the runway one two localizer at miami

14:13:25: End of CVR recording.

14:13:27 Tower critter five ninety two descend and maintain three thousand

14:13:43 Tower critter five ninety two opa locka airports aout ah twelve o’clock at fifteen miles

[End of Recording]

The cargo hold of this DC-9 was airtight.  This was its fire protection.  Because any fire would quickly consume any oxygen in the hold and burn itself out.  But also loaded in Flight 592’s hold were some oxygen generators.  The things that produce oxygen for passengers to breathe through masks that fall down during a loss of pressurization.  These produce oxygen through a chemical reaction that produces an enormous amount of heat.  These were hazardous equipment that were forbidden to be transported on the DC-9.  Some confusion in labeling led some to believe they were ’empty’ canisters when they were actually ‘expired’.  The crash investigation concluded that one of these were jostled on the ground and activated.  It produced an oxygen rich environment in the cargo hold.  And enough heat to start a smoldering fire.  Which soon turned into a raging inferno that burned through the cabin floor.  And through the flightdeck floor.  Either burning through all flight controls.  Or incapacitating the crew.  Sending the plane into a nose dive into the everglades in less than 4 minutes from the first sign of trouble.

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Girl sits on Phone in Back Pocket and starts Fire just as Damaged Batteries start Fires in Electric Cars

Posted by PITHOCRATES - February 2nd, 2014

Week in Review

Lithium-ion batteries are a wonder.  But they can be temperamental.  Which you can expect when you put highly reactive chemicals together.  Which is the price of higher energy storage densities.  Danger.  To make that charge last longer in the batteries powering our electronic devices.  And they can only do that by a chemical reaction that produces heat.  Boeing had a problem with their lithium-ion batteries that nearly caught a couple of their new Dreamliners on fire.  Resulting in an FAA grounding of the entire fleet until they found a way to make their batteries safer.  But it’s not just big lithium-ion batteries that can burst into flames (see iPhone catches fire, teen girl burned by Chris Matyszczyk posted 2/1/2014 on CNET).

An eighth-grader in Maine is sitting in class when she hears a pop. Then she notices smoke coming from her back pocket…

The culprit is said to have been her iPhone. Images suggest it had caught fire…

The division chief of the local emergency medical services, Andrew Palmeri, told Seacoast Online that the phone’s battery had “shorted out.” He suggested that the phone had been crushed in the teen’s back pocket. Local fire services are investigating…

Cell phones of whatever brand do catch fire. iPhones have caught fire on planes, just as Droids have exploded in ears.

So lithium-ion batteries can be dangerous.  Despite being the wonders they are.  For these chemical reactions are powerful.  And need to be confined perfectly.  But if you sit on a cell phone you can damage the confinement of those chemicals.  Causing a fire.  Just as accidents in electric cars have resulted in battery fires that have totaled these cars.  Or a faulty charging circuit started a fire overnight while charging in an attached garage.  Starting the house on fire.  Or nearly started a plane on fire.

The greatest hindrance to electric car sales is a thing called range anxiety.  Will I have enough charge to get home?  The answer to this problem is, of course, increasing the charge available in these cars.  Typically with bigger and more powerful batteries.  Which can burn the car to a crisp after an accident damages the battery.  Or debris on the roadway is thrown up by a tire into the battery.  Things that won’t total a gasoline-powered car if they happen.  Because gas is a high-density energy source.  Like these lithium-ion batters.  But it takes a lot more abuse to the gas tank to get it to start a fire.  Which is why electric cars will not replace the gasoline-powered car.  As they provide a far greater range and are safer.  And until the electric car can out do the gasoline-powered car on these two points the electric car will remain a novelty.

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Tunnels

Posted by PITHOCRATES - January 22nd, 2014

Technology 101

A Bridge is a Fixed Structure that requires no Active Systems to Function

Bridges are dumb.  While tunnels are smart.  You can build a bridge and walk away from it.  And it will still work.  That is, you can still cross the bridge without anyone at the bridge doing anything.  It can even work in a power outage.  Even at night.  It may be dark.  But a car’s headlights will let a person cross safely.  Because a bridge doesn’t have to do much for people to use it.  All it has to do is stand there.  A tunnel, on the other hand, needs smart systems to make the tunnel passable and safe.

Bridges are high in the air.  Where there is plenty of fresh air to breathe.  If there is a car fire on the bridge all of that fresh air will allow other drivers to breathe as they drive around it.  And for first responders to breathe as they put that fire out.  They can use all the water they bring onto the bridge, too.  Even in a driving downpour.  For that water will just run off of that bridge without causing a drowning hazard.  Visibility doesn’t change driving onto or off of the bridge.  Unlike with tunnels.  Where you can go from bright daylight into a dark hole.  And from a dark hole into bright daylight.

A bridge is a fixed structure that requires no active systems to function.  Just some maintenance.  Painting and roadway lighting.  Maybe some traffic control signals.  But that’s about it.  Tunnels, on the other hand, need machinery.  Equipment.  Systems.  And people.  Because tunneling below grade causes a whole host of problems.  Problems that have to be addressed with machinery, equipment and systems.  And if they don’t work people can die in a tunnel.

Powerful fans at each end of the tunnel pull in fresh air and blow it through the duct under the roadway

Cars have internal combustion engines.  They exhaust carbon monoxide after combustion.  Which is poisonous if we breathe it.  A big problem in tunnels filled with cars with internal combustion engines.  Which is why if you look at a cross-sectional view of a tunnel you will see that the biggest section of these underground structures are used for moving air.

If you have driven through a tunnel you probably remember driving through a rectangular tube.  Little bigger than the vehicles driving through it.  What you don’t see is the air duct beneath the roadway.  And the air duct above the roadway.  Powerful fans at each end of the tunnel pull in fresh air from the atmosphere and blow it through the duct under the roadway.  It exits the duct at about exhaust pipe level.  This fresh air blows into the rectangular tube where cars are pumping in carbon monoxide.

Other powerful fans are also located at each end of the tunnel that pull air out of the tunnel.  Via the duct over the roadway.  Fresh air comes in from below.  Mixes with the poisonous carbon monoxide.  This gets sucked into openings overhead.  Into the duct over the roadway.  And vents to the atmosphere at either end of the tunnel.  Allowing these poison-making machines to travel underground in an enclosed space without killing people.

A Tunnel is a Complex Machine that requires Intelligent Programming not to put People in Danger

Tunnels through mountains go through porous rock that drip water into the tunnel.  Tunnels under bodies of water are low in the middle and high at the ends.  Making each tunnel portal a massive storm drain when it rains.  And water in a tunnel is a dangerous thing.  It can freeze.  It can get deep.  It can cause an accident.  It can drown people.  So when it enters the tunnel you need to pump it out.  Tunnels have storm drains that drain any water entering the tunnel to a sump at a low point.  And pumps move this water from the sump out of the tunnel.

Ever spend an hour or so shoveling snow on a bright day?  And then go inside only to temporarily lose your vision?  This is snow blindness.  Your pupils shrink down to a tiny dot outside to block much of the bright sun and the light reflecting from the snow and ice. And when you walk inside that tiny dot of a pupil won’t let enough light into your eye so you can see in the reduced lighting level.  After awhile your pupils begin to dilate.  And you can see.  Same thing happens when driving into a tunnel.  Of course, temporarily losing your vision while driving a car can be dangerous.  So they add a lot of lights at the entrance of a tunnel.  To replicate sunlight.  And as you drive through the tunnel the lighting levels fall as your eyes adjust.  At night they reduce the lighting levels to prevent blinding drives as they enter.  And prevent snow blindness when exiting the tunnel.

A bridge doesn’t need any of these systems.  But a tunnel won’t work without them.  As people could die in these tunnels.  Because it’s dangerous when people go below grade with machines that create poison.  So tunnels need computers and control systems.  To monitor existing conditions such as exterior lighting levels, carbon monoxide levels, smoke and fire detection, water levels and high water alarms, etc.  Based on these inputs a control system (or a person) turns lights on or off, increase or decrease supply and exhaust fan speeds, pump down the sump when it reaches a high water level, etc.  Only when these systems are on line and operating properly is driving through a tunnel as safe as driving over a bridge.  Because bridges are dumb things.  They only need to stand there to work.  While a tunnel is a complex machine.  That requires intelligent programming not to put people in danger.

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A Third Tesla Model S is Consumed by Flames from their Lithium-Ion Batteries

Posted by PITHOCRATES - November 9th, 2013

Week in Review

There were two Boeing 787 Dreamliners that had a battery problem and a burning smell.  Fire is dangerous.  Especially in an airplane.  There was no loss of life in either incident.  And there was minor damage.  But two incidents were enough for the FAA to ground the entire Boeing 787 Dreamliner fleet.  Yes, fire is dangerous on an airplane.  But the government was also mad at Boeing for wanting to make the Dreamliner with nonunion labor.  Did this play a role in the grounding?  Who knows?

Tesla has now had three lithium-ion fires.  Not battery problems with a burning smell.  The federal government likes Tesla.  Wants everyone to drive an electric car.  And subsidizes the electric car industry.  Interestingly how Tesla can have three fires that destroy the car entirely and yet receive no scrutiny from the National Highway Traffic Safety Administration.  Guess the government thinks Boeing wants to put people on unsafe airplanes while Tesla doesn’t want to put people in unsafe cars (see Tesla reports third fire involving Model S electric car by Ben Klayman and Bernie Woodall, Reuters, posted 11/8/2013 on The Globe and Mail).

Tesla Motors Inc. reported the third fire in its Model S luxury electric car in six weeks, this time after a highway accident in Tennessee, sending shares down sharply on Thursday.

The Tennessee Highway Patrol said the 2013 model sedan ran over a tow hitch that hit the undercarriage of the vehicle, causing an electrical fire on Interstate 24 on Wednesday. A highway patrol dispatcher called the damage to the car “extensive.”

The Model S undercarriage has armour plating that protects a battery pack of lithium-ion cells. Tesla said it did not yet know whether the fire involved the car’s battery.

An electrical fire in an electric car probably involved the car’s battery.  For without gasoline and a source for ignition what else can burn in an electric car other than a high energy density device under heat and pressure?

The first Model S fire occurred on Oct. 1 near Seattle, when the car collided with a large piece of metal debris in the road that punched a hole through the protective armour plating…

The second fire took place later in the month in Merida, Mexico, when, according to reports, a car drove through a roundabout, crashed through a concrete wall and hit a tree…

While none of the drivers in any of the Tesla accidents were injured, the glaring headlines about fires were unwelcome for a company whose stock soared sixfold in the first nine months of the year. Since the first fire, Tesla’s shares have lost more than 27 per cent, and this week’s declines are the worst one-week drop since May, 2012.

“For a company with a stock price based as much or more on image than financials, those recurring headlines are highly damaging,” Kelley Blue Book senior analyst Karl Brauer said.

When image is more important than financials that means the electric car isn’t selling.  That the costs far exceed revenue.  And probably the only things allowing them to stay in business are government subsidies (both for Tesla and for Tesla buyers) and irrational exuberance.  Like when investors created a dot-com bubble in the late Nineties.  Bidding up stock prices into the stratosphere when companies had nothing to sell let alone profits.  At least in the dot-com bubble investors were betting that they found the next Microsoft and were going to get rich.  It’s a little more puzzling why investors are buying Tesla stock in the first place. 

Tesla may build the best electric cars in the world.  But they are still electric cars.  The problem is no one is buying electric cars.  Except rich people who can afford a third car.  With the other two being powered by gasoline.  In case they want to travel a long distance.  Or drive at night or in the cold with the lights and heat on.  Or have to rush a sick child to the hospital when the Tesla is on the charger.

Tesla’s battery pack is made up of small lithium-ion battery cells that are also used in laptop computers, an approach not used by other auto makers. The battery pack stretches across the base of the vehicle. In comparison, General Motors Co. uses large-format battery cells in a T-shape in the centre of the Chevrolet Volt plug-in hybrid car.

Other auto makers have dealt with battery fires in electrified vehicles, including GM’s Volt and Mitsubishi Motors Corp.’s i-MiEV…

“For consumers concerned about fire risk, there should be absolutely zero doubt that it is safer to power a car with a battery” than a conventional gas-powered vehicle, he said on a blog post.

Company executives called that first fire a “highly uncommon occurrence,” likely caused by a curved metal object falling off a semi-trailer and striking up into the underside of the car in a “pole-vault effect.”

Gasoline engines are dangerous, but Americans have learned to live with them over the years, said Tom Gage, the former CEO of AC Propulsion, which developed the drive train for Tesla’s first model, the Roadster.

“Obviously, gasoline can be lit more easily and can burn with more ferocity than a battery can, but a gas tank in a car now benefits from 120 years of fairly intensive development and government regulation regarding how you make it safe,” he said.

Ever smell gasoline?  In a parking lot?  When you shouldn’t?  It might have been more common in the old days.  When the Big Three were selling their rust buckets.  Which rusted out in the northern climates where they salt the roads during winter.  Salt makes metal rust.  Including gas tanks.  Causing leaks.  If you smelled gas, though, did you run away from that car and wait for it to explode?  No.  You didn’t.  You probably thought something along the lines of, “That guy should get that fixed.  Gasoline is too expensive to waste like that.”

And you can fix a leaky gas tank.  It’s dangerous but you can.  For a tank full of gas has more liquid than fumes in it.  But an empty gas tank may be full of lingering gas fumes.  That can explode if ignited with a welding torch.  Which is why before they weld a gas tank they fill it full of sand.  So there is no room for any explosive gas vapors.

Gasoline is flammable.  It will burn.  But it won’t explode.  For gasoline in a liquid form is not as dangerous as in other forms.  It can leak out of a gas tank.  And then evaporate into the atmosphere.  In a car wreck something can puncture the gas tank and cause fuel to spill out.  If this fuel is ignited it can burn.  And the fire will follow the gasoline back to the source.  If the fire reaches the gasoline fumes under pressure in the gas tank there can be an explosion.  A very big one at that.  But if the fire department is on the scene they can wash that gasoline away with a fire hose.  And prevent any fire or explosion.  When a lithium-ion battery burns, though, throwing water on it won’t do much.

For gasoline to power a gasoline-powered car we first have to vaporize it.  Mix it with oxygen (pulled from the air).  Compress the air-fuel mixture.  And then ignite it with a spark.  That’s when it’s dangerous.  When it’s inside our engines.  Not in the gas tank.  For a piece of metal can puncture the bottom of a car—including the gas tank—without causing a fire.  Whereas it’s a little iffy with a Tesla.  If something punctures the batteries covering the bottom of the car there’s a good chance there may be a fire.  While if you puncture a gas tank you may just run out of gas.

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Feedback Loop Control System

Posted by PITHOCRATES - October 30th, 2013

Technology 101

Living through Winters became easier with Thermostats

When man discovered how to make fire it changed where we could live.  We no longer had to follow the food south when winter came.  We could stay through the winter.  And build a home.  As long as we could store enough food for the winter.  And had fire to stay warm.  To prevent our dying from exposure to the cold.

There’s nothing like sitting around a campfire.  It’s warm.  And cozy.  In large part because it’s outside.  So the smoke, soot and ash stayed outside.  It wasn’t always like that, though.  We used to bring that campfire inside the home.  With a hole in the roof for the smoke.  And families slept around the fire.  Together.  Even as some fornicated.  To propagate the species.  But that wasn’t the worst part about living around an indoor campfire.

Your distance from the fire determined how hot or cold you were.  And it was very hot by it.  Not so hot away from it.  Especially with a hole in the roof.  Worst, everyone got colder as the fire burned out.  Meaning someone had to get up to start a new fire.  The hard way.  Creating an ember.  Using it to start some kindling burning.  Then adding larger sticks and branches onto the kindling until they started to burn.  Which was a lot harder than turning the thermostat to ‘heat’ at the beginning of the heating season and forgetting about it.  Then turning it to ‘off’ at the end of the heating season.

A Feedback Loop Control System measures the Output of a System and Compares it to a Desired Output

Replacing the indoor campfire with a boiler or furnace made life a lot simpler.  For with a supply of fuel (natural gas, fuel oil, electricity, etc.) the fire never burned itself out.  And you never had to get up to start a new one.  Of course, that created another problem.  Shutting it off.

Boilers and furnaces are very efficient today.  They produce a lot of heat.  And if you let them run all day long it would become like a hot summer day inside your house.  Something we don’t want.  Which is why we use air conditioners on hot summer days.  So heating systems can’t run all day long.  But we can’t keep getting up all night to turn it off when we’re too hot.  And turning it back on when we’re too cold.  Which is why we developed the feedback loop control system.

We did not develop the feedback loop control system for our heating systems.  Our heating systems are just one of many things we control with a feedback loop control system.  Which is basically measuring the output of a system and comparing it to a desired output.  For example, if we want to sleep under a cozy warm blanket we may set the ‘set-point’ to 68 degrees (on the thermostat).  The heating system will run and measure the actual temperature (at the thermostat) and compare it to the desired set-point.  That’s the feedback loop.  If the actual temperature is below the desired set-point (68 degrees in our example) the heat stays on.  Once the actual temperature equals the set-point the heat shuts off.

The Autopilot System includes Independent Control Systems for Speed, Heading and Altitude

Speed control on a car is another example of a feedback loop control system.  But this control system is a little more complex than a thermostat turning a heating system on and off.  As it doesn’t shut the engine off once the car reaches the set-point speed.  If it did the speed would immediately begin to fall below the set-point.  Also, a car’s speed varies due to terrain.  Gravity speeds the car when it’s going downhill.  And slows it down when it’s going uphill.  The speed controller continuously measures the car’s actual speed and subtracts it from the set-point.  If the number is negative the controller moves the vehicle’s throttle one way.  If it’s positive it moves the throttle in the other way.  The greater the difference the greater the movement.  And it keeps making these speed ‘corrections’ until the difference between the actual speed and the set-point is reduced to zero.

Though more complex than a heating thermostat the speed control on a car is pretty simple.  It has one input (speed).  And one output (throttle adjustment).  Now an airplane has a far more complex control system.  Often called just ‘autopilot’.  When it is actually multiple systems.  There is an auto-speed system that measures air speed and adjusts engine throttles.  There is a heading control system that measures the aircraft’s heading and adjusts the ailerons to adjust course heading.  There is an altitude control system that measures altitude and adjusts the elevators to adjust altitude.  And systems that measure and correct pitch and yaw.  Pilots enter set-points for each of these in the autopilot console.  And these control systems constantly measure actual readings (speed, heading and altitude) and compares them to the set-points in the autopilot console and adjusts the appropriate flight controls as necessary. 

Unlike a car or an airplane a building doesn’t move from point A to point B.  Yet they often have more complex control systems than autopilot systems on airplanes.  With thousands of inputs and outputs.  For example, in the summer there’s chilled water temperature, heating hot water temperature (for the summer boiler), supply air pressure, return air pressure, outdoor air pressure, indoor air pressure, outdoor temperature, outdoor humidity, indoor temperature (at numerous locations), indoor humidity, etc.  Thousands of inputs.  And thousands of outputs.  And unlike an airplane these are all integrated into one control system.  To produce a comfortable temperature in the building.  Maintain indoor air quality.  Keep humidity levels below what is uncomfortable and possibly damaging to electronic systems.  And prevent mold from growing.  But not keep it too dry that people suffer static sparks, dry eyes, dry nasal cavities that can lead to nose bleeds, dry and cracked skin, etc.  To prevent a blast of air hitting people when they open a door.  To keep the cold winter air from entering the building through cracks and spaces around doors and windows.  And a whole lot more.  Far more than the thermostat in our homes that turns our heating system on and off.

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Another Electric Car bursts into Flames

Posted by PITHOCRATES - October 5th, 2013

Week in Review

One thing we learned from Breaking Bad was to respect the chemistry.  And that’s what batteries are.  Chemistry.  The kind of chemistry that’s a little on the dangerous side.  Unlike gasoline.  Which we can store relatively safely in tanks under our cars.  Where little chemistry goes on inside our gas tanks.  To use that gasoline to power our cars we have to do a couple of things.  We have to aerosolize it.  Combine it with oxygen.  Compress it.  Then ignite it.  Then and only then does it release its incredible energy.  Producing great heat in the engine.  But not the gas tank.  Which needs no cooling system.  It’s a little different in an electric car.

In a battery the chemistry is all local.  It produces electricity—and heat—where the chemicals are stored.  In the battery.  One of the problems with electric cars is their limited range.  And you fix this problem with bigger and more powerful batteries.  That can produce a lot of electricity—and heat—as they charge or power the car.  Making battery cooling a requirement for safe battery use.  To keep those chemicals under control.  But sometimes these chemical reactions go out of control.  Causing fires as cars re-charge in their garages.  Causing fires that grounded the new Boeing 787 Dreamliner.  And this (see Hot Wheels! Tape of Tesla Fire Has Stock Tanking by Dan Berman, Hot Stock Minute, posted 10/3/2013 on Yahoo! Finance).

Tape of a Tesla (TSLA) on fire is giving new meaning to the term “hot wheels.” The video was shot on Tuesday after a Model S sedan went up in flames…

In an e-mail sent to The New York Times, Tesla spokeswoman Elizabeth Jarvis-Shean wrote that the fire was caused by the “direct impact of a large metallic object to one of the 16 modules within the Model S battery pack.” The e-mail went on to say, “Because each module within the battery pack is, by design, isolated by fire barriers to limit any potential damage, the fire in the battery pack was contained to a small section in the front of the vehicle.”

Contained to a small section?  It looks like the fire engulfed the whole car.  All because of some metal debris thrown up from the roadway.  Of course, a way to protect against something like this in the future is to add a metal shield that can take a direct hit without damage.  Adding a thick piece of metal under the car, though, adds weight.  Which, of course, reduces range.

This is a problem with electric cars.  Improving safety results in a reduction in range.  Because it adds weight.  It adds weight, too, with gasoline-powered cars.  But one full tank of gas can hold a lot more energy that all the batteries can on an electric car.  And when you run out of gas all you have to do is stop at a conveniently located gas station and fill up.  Which takes about 10 minutes or so.  Unlike a recharge of an electric car.  Which can take anywhere between a half hour (with a high-voltage fast charger) to overnight in the garage plugged into a standard outlet.  Which is why electric cars are more of a novelty.  Those who have them typically have other more reliable cars for their main driving needs.  For though gasoline-powered cars catch fire, too, when they’re not on fire you know you’re going to get home.

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Bucket Brigade, Fire Engine, Sprinkler System, Sprinkler Head, Fire Pump, Jockey Pump, Wet-Pipe and Dry-Pipe

Posted by PITHOCRATES - March 20th, 2013

Technology 101

A Fire Engine can move Water Faster and Farther with an Internal Combustion Engine than with a Steam Engine

Some of our earliest firefighters were bucket brigades.  Where people would form lines between a fire and a water source.  Someone would dip a bucket into the water source.  And then pass it to the next person in line.  Who would then pass it to the next person in line.  And so on until the bucket reached the person at the other end of the line.  Who then poured the water on the fire.  Then the empty buckets would work their way the other way back towards the water source.  Buckets of water moved from the source of water to the fire.  While empty buckets moved from the fire to the water source.

This was state of the art firefighting at the time.  As long as there were enough people to form a line from the water source to the fire.  The people didn’t tire out before the fire did.  And the fire wasn’t so large that buckets of water couldn’t put it out.  But soon we developed the hand-operated pump on our first fire engines.  And the fire hose.  Then we just had to run a fire hose from the water source to the fire engine.  And a fire hose from the fire engine to the fire.  People could take turns hand pumping, producing a steady stream of water.  That someone could direct onto a fire.  These new firefighting crews could put out large fires in shorter times.  Fire companies appeared in cities with trained firefighters.  Providing safer cities.  A great improvement over the bucket brigade.  But not as good as what came next.

Men pulled the early fire engines.  Then horses replaced men.  But the big advancement was in the fire pump.  When steam power replaced hand power.  Allowing greater flows of water at higher pressures.  Allowing firefighters to attack a fire from a safer distance.  But steam had some drawbacks.  It took time to boil water into steam.  Steam engines needed boiler operators to carefully operate the boiler so it didn’t explode.  And being an external combustion engine there were a lot of moving parts in the open.  That could be dangerous to the firefighters.  And being exposed to the elements they needed constant oiling.  The internal combustion engine didn’t suffer any of these drawbacks.  The modern fire engine is safer.  Easier to operate.  More efficient.  And can move more water faster and farther.

A Jockey Pump in a Sprinkler System maintains the Water Pressure when there’s no Fire

But even the modern fire engine has one drawback.  We park them at firehouses.  While all our fires are not at firehouses.  So they have to drive to the fire.  Which they can do pretty quickly.  But that’s still time a fire can grow.  Causing more damage.  Become stronger.   And more difficult to put out.  Which is why we brought fire-fighting water into buildings.  To use on a fire even before the fire department arrives on the scene.  Buildings today have fire sprinkler systems.  Pipes filled with water covering every square inch of a building.  That will release their water through the various sprinkler heads attached to these pipes.

The sprinkler head is a marvel of low-tech.  It is basically a threaded fitting that screws into the water-filled pipe.  The sprinkler head has a hole in it.  A glass bulb with a liquid inside of it holds a plug in the hole.  Preventing the flow of water.  If there is a fire under this head the heat will cause the liquid in the glass bulb to expand.  Eventually shattering the glass bulb.  The water pressure inside the pipe will blow out the plug.  Allowing the water to flow out of the pipe.  As it does it hits a deflector, producing a spray pattern that will evenly cover the area underneath the head.  Only areas where there is a fire will break these glass bulbs.  So only the sprinklers over fires will discharge their water.  Preventing water damage in areas where there is no fire.

Some buildings can operate off of city water pressure.  But larger buildings, especially multistory buildings, need help to maintain the water pressure in the system.  These buildings have fire pumps.  A large pump that can maintain the pressure in the sprinkler lines even if all the sprinkler heads are discharging water.  And a smaller jockey pump.  Which maintains the pressure in the system when there is no fire.  If the pressure drops below a lower limit the jockey pump comes on.  When the pressure rises above a higher limit the jockey pump shuts down.  If there is a fire in the building the fire pump will run until it melts down.  Putting water on the fire as long as it can.

A Dry-Pipe Fire Sprinkler System in an Unheated Area is often attached to a Wet-Pipe System in a Heated Area

If water would greatly damage an area (such as a hardwood basketball court) they may add a valve on the pipe feeding the sprinkler piping over the floor.  Keeping the water out of the pipes over the expensive hardwood floor.  Smoke detectors in the ceiling will open the valve when they detect a fire.  Letting water flow into the sprinkler lines over the floor.  And out of any sprinkler head over a fire hot enough to have broken the glass bulb to release the plug.

Water damage is a real concern.  For it may be a better alternative to fire damage.  But water damage in absence of any fire can be costly.  Something many have seen working on a new building in a northern climate.  During the first freeze.   If there was missed insulation on an exterior wall.  Under-designed heating in an exterior glass-enclosed stairwell.  Or both in a glass-enclosed vestibule that juts outside of a heated building.  As temperatures fall cold air migrates around these sprinkler lines.  Freezing the water inside.  Causing them to burst.  And when they do it releases the water pressure behind these frozen sections.  Flooding these areas with water.  Causing a lot of damage.  Not to mention the damage to the fire sprinkler system.

Some unheated areas need a sprinkler system.  But these pipes can’t be a wet-pipe system.  Because if there was water in the pipes it would freeze.  Breaking the pipes.  So we use a dry-pipe system in unheated areas.  Which is often attached a wet-pipe system.  Such as a dry-pipe system in an exterior canopy attached to a heated building.  There is a valve between the interior wet-pipe system and the exterior dry-pipe system.  An air compressor will put air under pressure in the dry-pipe system.  This air pressure will hold the valve close to the wet-pipe system.  If there is a fire underneath the canopy the glass bulb in a sprinkler head will expand and break.  Releasing the air from the dry-pipe system.  Allowing the water pressure in the wet-pipe system to open the valve.  Flooding the dry-pipe system.  And flowing out of the sprinkler head over the fire.

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Fire, Oil Lamp, Candle, Wicks, Gas Lights, Incandescence, Incandescent Light Bulb, Fluorescence and Compact Fluorescent Lamp

Posted by PITHOCRATES - February 20th, 2013

Technology 101

(Originally published March 28th, 2012)

A Lit Match heats the Fuel Absorbed into a Wick, Vaporizes it, Mixes it with Oxygen and Ignites It

Fire changed the world.  From when Homo erectus first captured it.  Around 600,000 BC.  In China.  They saw it.  Maybe following a lightning strike.  Seeing it around volcanic activity.  Perhaps a burning natural gas vent.  Whatever.  They saw fire.  Approached it.  And learned not to fear it.  How to add fuel to it.  To transfer it to another fuel source.  To carry it.  They couldn’t create fire.  But they could manage it.  And use it.  It was warm.  And bright.  So they brought it indoors.  To light up their caves.  Scare the predators out.  To use it to heat.  And to cook.  Taking a giant leap forward for mankind.

When man moved into man-made dwellings they brought fire with them.  At first a one-room structure with a fire in the center of it.  And a hole in the roof above it.  Where everyone gathered around to eat.  Stay warm.  Sleep.  Even to make babies.  As there wasn’t a lot of modesty back then.  Not that anyone complained much.  What was a little romance next to you when you were living in a room full of smoke, soot and ash?  Fireplaces and chimneys changed all that.  Back to back fireplaces could share a chimney.  Providing more heat and light.  Less smoke and ash.  And a little privacy.  Where the family could be in one room eating, staying warm, reading, playing games and sleeping.  While the grownups could make babies in the other room.

As we advanced so did our literacy.  After a hard day’s work we went inside.  After the sun set.  To read.  Write letters.  Do some paperwork for the business.  Write an opera.  Whatever.  Even during the summer time.  When it was warm.  And we didn’t have a large fire burning in the fireplace.  But we could still see to read and write.  Thanks to candles.  And oil lamps.  One using a liquid fuel.  One using a solid fuel.  But they both operate basically the same.  The wick draws liquid (or liquefied) fuel via capillary action.  Where a porous substance placed into contact with a liquid will absorb that liquid.  Like a paper towel or a sponge.  When you place a lit match into contact with the wick it heats the fuel absorbed into the wick and vaporizes it.  Mixing it with the oxygen in the air.  And ignites it.  Creating a flame.  The candle works the same way only starting with a solid fuel.  The match melts the top of this fuel and liquefies it.  Then it works the same way as an oil lamp.  With the heat of the flame melting the solid fuel to continue the process.

Placing a Mantle over a Flame created Light through Incandescence (when a Heated Object emits Visible Light)

Two popular oils were olive oil and whale oil.  Beeswax and tallow were common solid fuels.  Candles set the standard for noting lighting intensity.  One candle flame produced one candlepower.  Or ‘candela’ as we refer to it now.   (Which equals about 13 lumens – the amount of light emitted by a source).  If you placed multiple candles into a candelabrum you could increase the lighting intensity.  Three candles gave you 3 candela of light to read or write by.  A chandelier with numerous candles suspended from the ceiling could illuminate a room.  This artificial light shortened the nights.  And increased the working day.  In the 19th century John D. Rockefeller gave the world a new fuel for their oil lamps.  Kerosene.  Refined from petroleum oil.  And saved the whales.  By providing a more plentiful fuel.  At cheaper prices.

By shortening the nights we also made our streets safer.  Some cities passed laws for people living on streets to hang a lamp or two outside.  To light up the street.  Which did indeed help make the streets brighter.  And safer.  To improve on this street lighting idea required a new fuel.  Something in a gas form.  Something that you could pump into a piping system and route to the new street lamps.  A gas kept under a slight pressure so that it would flow up the lamp post.  Where you opened the gas spigot at night.  And lit the gas.  And the lamp glowed until you turned off the gas spigot in the morning.  Another advantage of gas lighting was it didn’t need wicks.  Just a nozzle for the gas to come out of where you could light it.  So there was no need to refuel or to replace the wicks.  Thus allowing them to stay lit for long periods with minimum maintenance.  We later put a mantle over the flame.  And used the flame to heat the mantle which then glowed bright white.  A mantle is like a little bag that fits over the flame made out of a heat resistant fabric.  Infused into the fabric are things that glow white when heated.  Rare-earth metallic salts.  Which change into solid oxides when heated to incandescence (when a heated object emits visible light).

One of the first gases we used was coal-gas.  Discovered in coal mines.  And then produced outside of a coal mine from mined coal.  It worked great.  But when it burned it emitted carbon.  Like all these open flames did.  Which is a bit of a drawback for indoor use.  Filling your house up with smoke.  And soot.  Not to mention that other thing.  Filling up your house with open flames.  Which can be very dangerous indoors.  So we enclosed some of these flames.  Placing them in a glass chimney.  Or glass boxes.  As in street lighting.  Enclosing the flame completely (but with enough venting to sustain the flame) to prevent the rain form putting it out.  This glass, though, blackened from all that carbon and soot.  Adding additional maintenance.  But at least they were safer.   And less of a fire hazard.  Well, at least less of one type of fire hazard.  From the flame.  But there was another hazard.  We were piping gas everywhere.  Outside.  Into buildings.  Even into our homes.  Where it wasn’t uncommon for this gas to go boom.  Particularly dangerous were theatres.  Where they turned on the gas.  And then went to each gas nozzle with an open fire on a stick to light them.  And if they didn’t move quickly enough the theatre filled with a lot of gas.  An enclosed space filled with a lot of gas with someone walking around with an open fire on a stick.  Never a good thing.

Fluorescent Lighting is the Lighting of Choice in Commercial, Professional and Institutional Buildings

Thomas Edison fixed all of these problems.  By finding another way to produce incandescence. By running an electrical current through a filament inside a sealed bulb.  The current heated the filament to incandescence.  Creating a lot of heat.  And some visible light.  First filaments were carbon based.  Then tungsten became the filament of choice.  Because they lasted longer.  At first the bulbs contained a vacuum.  But they found later that a noble gas prevented the blackening of the bulb.  The incandescent light bulb ended the era of gas lighting.  For it was safer.  Required less maintenance.  And was much easier to operate.  All you had to do was flick a switch.  As amazing as the incandescent light bulb was it had one big drawback.  Especially when we use a lot of them indoors.  That heat.  As the filament produced far more heat than light.  Which made hot buildings hotter.  And made air conditioners work harder getting that heat out of the building.  Enter the fluorescent lamp.

If phosphor absorbs invisible short-wave ultraviolet radiation it will fluoresce.  And emit long-wave visible light.  But not through incandescence.  But by luminescence.  Instead of using heat to produce light this process uses cooler electromagnetic radiation.  Which forms the basis of the fluorescent lamp.  A gas-discharge lamp.  The most common being the 4-foot tube you see in office buildings.  This tube has an electrode at each end.  Contains a noble gas (outer shell of valence electrons are full and not chemically reactive or electrically conductive) at a low pressure.  And a little bit of mercury.  When we turn on the lamp we create an electric field between the electrodes.  As it grows in intensity it eventually pulls electrons out of their valence shell ionizing the gas into an electrically conductive plasma.  This creates an arc between the electrodes.  This charged plasma field excites the mercury.  Which produces the invisible short-wave ultraviolet radiation that the phosphor absorbs.  Causing fluorescence.

One candle produces about 13 lumens of light.  Barely enough to read and write by.  Whereas a 100W incandescent light bulb produces about 1,600 lumens.  The equivalent of 123 candles.  In other words, one incandescent lamp produces the same amount of light as a 123-candle chandelier.  Without the smoke, soot or fire hazard.  And the compact fluorescent lamp improves on this.  For a 26W compact fluorescent lamp can produce the lumen output of a 100W incandescent light bulb.  A one-to-one tradeoff on lighting output.  At a quarter of the power consumption.  And producing less heat due to creating light from fluorescence instead of incandescence.  Making fluorescent lighting the lighting of choice in commercial, professional and institutional buildings.  And any other air conditioned space with large lighting loads.

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