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.



Tags: , , , , , , , , , , , , , , , , , ,

Melting Snow and Ice

Posted by PITHOCRATES - February 5th, 2014

Technology 101

When Temperatures fall below Freezing Liquid Water turns into Solid Water

You know what the best thing about water is?  You don’t have to shovel it.  Well, that, and its life-giving properties.  Let’s face it.  We couldn’t survive without the stuff.  We couldn’t grow food.  We even couldn’t live without drinking water.  So perhaps its life-giving properties is the best thing about water.  But a close second would be that thing about not having to shovel it.

When it rains water soaks into our green areas.  It runs off driveways and sidewalks into green areas.  And into streets.  Where it runs off into a storm drainage system.  Which takes it to a river or lake.  The rain lets our gardens grow.  And any excess water conveniently just goes away.  We may have a puddle or two to slosh through.  But even those go away without us having to do anything.  Water is nice that way.  As long as the temperature is above its freezing point.

When the temperature falls below the freezing point of water bad things start to happen.  Liquid water turns into solid water.  And hangs around for awhile.  Accumulating.  On our driveways, sidewalks, porches and roads.  It’s pretty much everywhere we don’t want it to be.  Making it difficult to walk.  And drive.  We slip and fall a lot in it.  The sun may melt it a little during the day.  Creating puddles of water where the snow once was. But when the sun sets those puddles freeze.  And become even more slippery.  Making solid water more dangerous than liquid water.  So a big part of making it through winters in northern climes, then, is transforming solid water back into the liquid form.

Even though Bourbon melts Ice Cubes Bourbon would be a Poor Choice to melt Snow and Ice

All material can be in three different stages.  It can be a solid.  A liquid.  Or a gas.  What determines the phase of this material depends on a couple of things.  Mostly temperature and pressure.  And the chemical properties of the material.  At ambient temperature and pressure material typically exists stably in one phase.  Water, for example, is stable in the liquid phase on an 80-degree summer day.  Allowing us to swim in it.  While on a freezing February day it is stable in the solid phase.  Which is why we hold the Winter Olympics in February.  The cold temperatures give us the best solid water conditions.

If we raise the temperature of water we can turn it from a liquid to a gas.  We could also do this by lowering the ambient air pressure.  Such as putting it into a vacuum.  For a liquid remains a liquid as long as the vapor pressure (the tendency for particles to escape from the liquid they’re in) of the liquid is less than the ambient air pressure.  If we lower the ambient air pressure below the vapor pressure of the liquid we can lower the boiling point of that liquid.  This is why different liquids have different boiling points.  They have different vapor pressures.  Oxygen has a very high vapor pressure and requires a high pressure and cold temperature to keep oxygen in a liquid phase.

When we take ice cubes out of the freezer and add them to a glass of bourbon they melt.  Because the ambient temperature outside of the freezer is above the freezing point of water.  So the solid water changes its phase from solid to liquid.  It would follow, then, that pouring bourbon on snow and ice would help melt it.  Of course we don’t do that.  For wasting bourbon like that would be criminal.  Not to mention costly.  Even if you used the cheap stuff.  Making bourbon a poor choice for melting snow and ice.

Salt dissolves into a Brine Solution that lowers the Melting Point of Snow and Ice

We see that a material will change its phase at different temperatures and pressures.  Which is good to know.  But it doesn’t help us to melt snow and ice during winter.  For we can’t lower the atmospheric air pressure to lower the boiling and melting points of water.  And we can’t raise the ambient temperature above the melting point of water.  If we could our winters would probably be a lot more comfortable than they are now.  So because when we can’t change the air pressure or temperature of the ambient environment the snow and ice is in we do something else.  We use chemistry to lower the melting point of snow and ice.  And the most common chemical we use is salt.

To melt snow and ice salt needs heat and moisture.  The moisture comes from the snow and ice.  Or from the humidity in the air.  The heat comes from the warmth of the earth or air.  Heated by the sun.  It also comes from the friction between tires and the road.  When salt comes into contract with water and heat it dissolves into a brine solution.  And this brine solution has a much lower melting point than water.  Which in turn lowers the melting point of the snow and ice it comes into contact with.  Allowing it to be in the liquid phase at temperatures below freezing temperatures.  Melting that snow and ice so it can run off like rain water.

The warmer it is when it snows the quicker salt will melt that snow.  While the colder it is the longer it takes to melt.  If it gets too cold (around 15 degrees Fahrenheit) salt proves to be ineffective.  In temperatures below 15 degrees Fahrenheit other chemicals work better.  Such as calcium chloride.  But calcium chloride is more costly than sodium chloride (salt).  Ambient temperatures, time of day, sunny or cloudy, wind, etc., all determine the chemical to use.  And the amount of chemical to use.  They consider all of these factors (and more) before sending those ‘salt’ trucks out on the roads.  Allowing us to drive in the worst of winters just as we drive in the best of summers.  It may take more time.  And there may be a little more cussing.  But we still go to work, take our kids to school, go shopping, etc., when it snows.  Thanks to chemicals.  Chemistry.  And the people that put those chemicals and that chemistry to work.



Tags: , , , , , , , , , , , , , , , , , , , , , , , , , ,

Fighting a Fire in Sub-Freezing Temperatures Shows how Global Warming is better than Global Cooling

Posted by PITHOCRATES - January 25th, 2014

Week in Review

The left has been warning us about the global warming apocalypse since the Nineties.  And how the warming of the planet will kill us. But global warming is not high on the list of concerns for many these days.  Especially during brutally cold weather of late (see About 35 feared dead in Quebec senior citizens’ home fire by The Associated Press posted 1/24/2014 on The Washington Times).

Using steam to melt the ice, investigators searched the frozen-over ruins of a retirement home Friday for victims of a fire that left about 35 people feared dead and cast such a pall over the village of 1,500 that psychologists were sent door to door.

The spray from firefighters’ hoses left the senior citizens home resembling a macabre snow palace, the ruins encased in thick white ice dripping with icicles.

Search teams of police, firefighters and coroners slowly and methodically went through the ruins, working in shifts in the extreme cold about 140 miles (225 kilometers) northeast of Quebec City. The afternoon temperature was around 3 degrees F (minus 16 Celsius.)…

Hivon said the home was up to code and had a proper evacuation plan. A Quebec Health Department document indicates the home which has operated since 1997, had only a partial sprinkler system. The home expanded around 2002, and the sprinklers in the new part of the building triggered the alarm.

The cold caused fire equipment to freeze, and firefighters used so much water that they drained the town reservoir.

Warm is better than cold.  For we can survive in warm better than we can in cold.  Here’s a fire in northern Quebec that became a dangerous labyrinth of ice as they fought a fire.  Yet just another example of how dangerous cold can be.

The last of the great famines that weren’t manmade (like those resulting from the communism of Stalin or Mao or the current dictator in North Korea) were during the little ice age.  When global temperatures cooled slightly.  Shortening the growing season.  Thus diminishing the food supply.  And without sufficient food people die.  This is the danger of climate.  Cooling.  For we can handle global warming.  As long as it’s warm we can grow food.  If the soil is too dry we can irrigate.  If it doesn’t rain we can irrigate the land with desalinated seawater.  Of which there is a never ending supply of in the world’s oceans.  And we can turn seawater into fresh water with the energy from nuclear power plants that provide our electricity to drive our air conditioners during the greatest of heat waves.

If it’s warm there is no limit to what man can do.  If the world is covered in snow and ice, though, not even man can save the human race.  Unless, that is, manmade global warming is real.  If so then man could warm an ice age and grow the food to sustain the human race.

Global warming?  Pish tosh.  The great civilizations arose once man took control of his environment.  And if he’s warming it so much the better.  For that just means longer growing seasons and more food to sustain a growing world population.



Tags: , , , , , , , , , ,


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.



Tags: , , , , , , , , , , , , , , , , , , , , ,

FT203: “People vacationing in warmer climes know global warming is better than global cooling.” —Old Pithy

Posted by PITHOCRATES - January 3rd, 2014

Fundamental Truth

It is very rare for People to Vacation somewhere where they have to wear more Clothes

People love a white Christmas.  Looking out your front window as a gentle snow falls.  Christmas lights and reindeer on the lawn poking out from the fields of snow.  Coming in from the cold and shaking the snow off.  Then warming up with a cup of cocoa in front of the fireplace.  Feeling the warmth radiate out while listening to the pops of the burning wood.  The warm memories of Christmases past.  Then comes New Year’s Day.  And then you just hate that foul white stuff as you shovel it for the umpteenth time.

As you shovel and your back aches and you feel what may have been a hernia you now understand why people retire to someplace warm.  To get away from this.  Before they have a heart attack shoveling it.  Because you’re sick and tired of shoveling snow.  Cleaning the snow off your car.  Fearing for your life when cars ahead of you spinout.  Wondering how many times can you slip and fall before you start breaking something.  But most of all you just hate being cold.  All you can think about is the joy of last summer sitting in the shade with a cold beer.  Doing nothing.  And loving it.

Even young and healthy college kids hate the cold.  Which is why when they go on spring break they head south.  And between the boozing and the sex they spend time lying on the beach doing nothing.  And loving it.  With the ladies practically naked in tiny bikinis sunning themselves.  And the men looking at the practically naked ladies.  For it is very rare for any vacationer (other than those on a ski getaway) to vacation somewhere where they have to wear more clothes.  Because people just don’t like being cold.

The Fall Harvest feeds most People most of the Year

But we complain when it’s too hot, too.  During the dog days of summer.  When it’s the humidity, not the heat, that makes it so insufferable.  Until we step inside our air conditioned home.  Or sit in an air conditioned movie.  While enjoying a cool beverage.  And some delicious popcorn.  Or spend time in the pool.  Or at the beach.  Where the ladies are practically naked.  Or going out to eat.  Enjoying cool adult beverages and a nice meal at an outdoor cafe while wearing shorts.  Or dining inside an air conditioned restaurant.

You may sweat and stink when you get home.  But you won’t be tracking snow and salt into the house.  Soaking the rugs and carpets.  Or leaving puddles of water on the tiled floor.  No.  During the summer there’s no mess.  There are no wet socks in your shoes.  No frost bite.  No hypothermia. If you car breaks down in the summer you don’t have to worry about freezing to death before someone rescues you.  Whereas if you slip off the road and down the embankment on an expressway during a blizzard frostbite and hypothermia are real possibilities.  As is freezing to death.  Because being cold is dangerous.  And being cold when you’re stranded a long way from home or help can be lethal.

Another bad thing about cold is that things don’t grow in the cold.  Which is why farming is seasonal.  A problem throughout history.  As people’s need to eat is not seasonal.  So not only did farmers have to grow food to eat during the summer they had to grow enough during the summer to feed everyone throughout the winter.  With the fall harvest feeding most people most of the year.  Making a long growing season essential for survival.  Because if you ran out of food before the next harvest you went hungry.  Or died.

If we have another Little Ice Age we may suffer Recurring Famines once More

There were recurring famines during the Little Ice Age.  Which ran from approximately 1350 to about 1850.  The climate cooled enough to shorten the growing season.  Which were cooler and wetter than they are today.  And because of that they didn’t grow enough food to feed everyone.  With the occasional famine wiping out about 10% or more of a country’s population.  As masses of people starved to death because of global cooling during the Little Ice Age.

The United States suffered some droughts the past few growing seasons.  And food prices went up because of these droughts.  But there were no famines in the United States.  Or in the countries the United States exports food to.  No, today the only countries having recurring famines are hard-line communist or other such closed and oppressive states.  Such as North Korea.  Al Gore has been warning us about the perils of global warming since the Nineties.  We did nothing.  And a few decades later there are still no famines.  Because even in regions suffering from the worst drought farmers can still irrigate their land.  And grow food.  Food may be more costly but there will be food.  But no famine.

People who worry about global warming fret about these droughts.  And the lack of fresh water.  But about 70% of the earth is nothing but ocean.  And we can desalinize seawater.  It’ll make water more costly.  But there will always be water.  Even during the worst of droughts.  So even if global warming does its worst to us we will be all right.  No.  The real fear is global cooling.  Because global cooling will shorten our growing seasons.  Which will reduce our food supply.  And if you ever looked at an aerial view of our vast farmland you will understand the problem that is.  It’s just too big to bring indoors.  If we have another Little Ice Age we may suffer recurring famines once more.  And not just in North Korea.  But throughout the world.  Those people vacationing in warmer climes know it.  Global warming is better than global cooling.  For our personal comfort and safety.  And our food supply.



Tags: , , , , , , , , , , , , , , , , , , , , , , ,

The Calendar and Irrigation

Posted by PITHOCRATES - December 4th, 2013

Technology 101

(Originally published November 16th, 2011)

The Nile is a Sliver of Life-Sustaining Black Earth Carved through the Lifeless Red Earth of the Desert

The early Egyptians were a religious people.  They still are today.  Egypt is a special land.  A unique land.  Because the Nile River flows through it on its way to the Mediterranean Sea.

The Nile is the source of life.  For it was the Nile that allowed farming.  Because of fresh water.  And fertile soil.  Black earth.  The rich silt that the Nile washed down from on high.  Beyond the First Cataract.  All the way to its headwaters.  Where monsoons in the Ethiopian Plateau, around Lake Victoria and in the Ruwenzori mountains flowed into the Blue Nile and the White Nile.  That joined into the Nile and flowed down to the Mediterranean Sea.  Bringing with it the rich silt that flooded over the riverbanks.  And left behind some of the richest soil ever farmed.

The life from the Nile was a miracle.  A blessing for the Egyptians.  This sliver of life-sustaining black earth carved through the lifeless red earth of the desert.  So they prayed.  And they worshipped.  To placate the gods.  To keep the miracle of black earth returning harvest after harvest.  For when the gods favored them the flooding came.  On time.  And at just the right height.  But when the gods did not there was famine.

By Tracking a Regular Cycle of Natural Events they Knew When to Worship and What to Do in the Farming Cycle

If the gods favored them the flooding was predictable.  If Khnum favored them the First Cataract would bring on the floodwaters at the right time and in the right amount.  Thoth would foretell this in the form of white ibises returning from their southern migration.  A favorable omen of a good harvest.  Which began with the sowing.  The grain representing Osiris’ body.  A god killed by another god.  Seth.  Who embodied the lifeless red earth.  The new growth was the resurrection of Osiris.  At the harvest they praised Isis.  For the resurrection.  That was the harvest.

The Egyptians were a religious people.  Religious ceremonies and rituals occurred throughout the farming cycle.  It’s no surprise, then, that the Egyptians created one of the first calendars.  Which marked important religious ceremonies and rituals.  And the cycle of farming.

By being able to track this regular cycle of natural events they knew when to worship.  What to do in the farming cycle.  When to do it.  And they knew when something was wrong.  For one day the floods did not come.  The climate had changed.  And the water didn’t come to them from the river.  So they had to go to the water in the river.

When the Nile didn’t Flood when the Calendar said it Should we Created Irrigation

As agriculture developed so did our understanding of our environment.  And we developed a lot of this with our religious beliefs.  For our environment was the blessing of the gods.  And at times their curse.  But our observations grew.  As did our understanding.  We developed the calendar.  And when the Nile didn’t flood when the calendar said it should we created irrigation.  Expanding the lands under cultivation.  And grew even more food.  For even though the Nile didn’t flood the water and silt were still there.

Our initial religious beliefs may not have properly explained the flooding of the Nile.  But it was a first step in our critical thinking.  Trying to explain that which we didn’t understand.  We may have been wrong about the cause.  But we got a pretty good understanding of the seasons.  By studying our environment.  And learning how to change it to suit our needs.  And it’s this critical thinking that led the way to irrigation.  And, eventually, to the modern civilization.



Tags: , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

Steam Locomotive

Posted by PITHOCRATES - November 13th, 2013

Technology 101

The Steam Locomotive was one of the Few Technologies that wasn’t replaced by a Superior Technology 

Man first used stone tools about two and a half million years ago.  We first controlled fire for our use about a million years ago.  We first domesticated animals and began farming a little over 10,000 years ago.  The Egyptians were moving goods by boats some 5,000 years ago.  The Greeks and Romans first used the water wheel for power about 2,500 years ago. The Industrial Revolution began about 250 years ago.  James Watt improved the steam engine about 230 years ago.  England introduced the first steam locomotive into rail service about 210 years ago. 

In the first half of the 1800s the United States started building its railroads.  Helping the North to win the Civil War.  And completing the transcontinental railroad in 1869.  By 1890 there were about 130,000 miles of track crisscrossing the United States.  With the stream locomotives growing faster.  And more powerful.  These massive marvels of engineering helped the United States to become the number one economic power in the world.  As her vast resources and manufacturing centers were all connected by rail.  These powerful steam locomotives raced people across the continent.  And pulled ever longer—and heavier—freight trains.

We built bigger and bigger steam locomotives.  That had the power to pull freight across mountains.  To race across the Great Plains.  And into our cities.  With the chugging sound and the mournful steam whistle filling many a childhood memories.  But by the end of World War II the era of steam was over.  After little more than a century.  Barely a blip in the historical record.  Yet it advanced mankind in that century like few other technological advances.   Transforming the Industrial Revolution into the Second Industrial Revolution.  Or the Technological Revolution.  That gave us the steel that built America.  Electric Power.  Mass production.  And the production line.  None of which would have happened without the steam locomotive.  It was one of the few technologies that wasn’t replaced by a superior technology.  For the steam locomotive was more powerful than the diesel-electric that replaced it.  But the diesel-electric was far more cost-efficient than the steam locomotive. Even if you had to lash up 5 diesels to do the job of one steam locomotive.

The Hot Gases from the Firebox pass through the Boiler Tubes to Boil Water into Steam

The steam engine is an external combustion engine.  Unlike the internal combustion engine the burning of fuel did not move a piston.  Instead burning fuel produced steam.  And the expansion energy in steam moved the piston.  The steam locomotive is a large but compact boiler on wheels.  At one end is a firebox that typically burned wood, coal or oil.  At the other end is the smokebox.  Where the hot gases from the firebox ultimately vent out into the atmosphere through the smokestack.  In between the firebox and the smokebox are a bundle of long pipes.  Boiler tubes.  The longer the locomotive the longer the boiler tubes. 

To start a fire the fireman lights something to burn with a torch and places it on the grating in the firebox.  As this burns he may place some pieces of wood on it to build the fire bigger.  Once the fire is strong he will start shoveling in coal.  Slowly but surely the fire grows hotter.  The hot gases pass through the boiler tubes and into the smokebox.  And up the smoke stack.  Water surrounds the boiler tubes.  The hot gases in the boiler tubes heat the water around the tubes.  Boiling it into steam.  Slowly but surely the amount of water boiled into steam grows.  Increasing the steam pressure in the boiler.  At the top of the boiler over the boiler tubes is a steam dome.  A high point in the boiler where steam under pressure collects looking for a way out of the boiler.  Turned up into the steam dome is a pipe that runs down and splits into two.  Running to the valve chest above each steam cylinder.  Where the steam pushes a piston back and forth.  Which connects to the drive wheels via a connecting rod.

When the engineer moves the throttle level it operates a variable valve in the steam dome.  The more he opens this valve the more steam flows out of the boiler and into the valve chests.  And the greater the speed.  The valve in the valve chest moved back and forth.  When it moved to one side it opened a port into the piston cylinder behind the piston to push it one way.  Then the valve moved the other way.  Opening a port on the other side of the piston cylinder to allow steam to flow in front of the piston.  To push it back the other way.  As the steam expanded in the cylinder to push the piston the spent steam exhausted into the smoke stack and up into the atmosphere.  Creating a draft that helped pull the hot gases from the firebox through the boiler tubes, into the smokebox and out the smoke stack.  Creating the chugging sound from our childhood memories.

The Challenger and the Big Boy were the Superstars of Steam Locomotives

To keep the locomotive moving required two things.  A continuous supply of fuel and water.  Stored in the tender trailing the locomotive.  The fireman shoveled coal from the tender into the firebox.  What space the coal wasn’t occupying in the tender was filled with water.  The only limit on speed and power was the size of the boiler.  The bigger the firebox the hotter the fire.  And the hungrier it was for fuel.  The bigger locomotives required a mechanized coal feeder into the firebox as a person couldn’t shovel the coal fast enough.  Also, the bigger the engine the greater the weight.  The greater the weight the greater the wear and tear on the rail.  Like trucks on the highway railroads had a limit of weight per axel.  So as the engines got bigger the more wheels there were ahead of the drive wheels and trailing the drive wheels.  For example, the Hudson 4-6-4 had two axels (with four wheels) ahead of the drive wheels.  Three axles (with 6 wheels) connected to the pistons that powered the train.  And two axels (with four wheels) trailing the drive wheels to help support the weight of the firebox.

To achieve ever higher speeds and power over grades required ever larger boilers.  For higher speeds used a lot of steam.  Requiring a huge firebox to keep boiling water into steam to maintain those higher speeds.  But greater lengths and heavier boilers required more wheels.  And more wheels did not turn well in curves.  Leading to more wear and tear on the rails.  Enter the 4-6-6-4 Challenger.  The pinnacle of steam locomotive design.  To accommodate this behemoth on curves the designers reintroduced the articulating locomotive.  They split up the 12 drive wheels of the then most powerful locomotive in service into two sets of 6.  Each with their own set of pistons.  While the long boiler was a solid piece the frame underneath wasn’t.  It had a pivot point.  The first set of drive wheels and the four wheels in front of them were in front of this pivot.  And the second set of drive wheels and the trailing 4 wheels that carried the weight of the massive boiler on the Challenger were behind this pivot.  So instead of having one 4-6-6-4 struggling through curves there was one 4-6 trailing one 6-4.  Allowing it to negotiate curves easier and at greater speeds.

The Challenger was fast.  And powerful.  It could handle just about any track in America.  Except that over the Wasatch Range between Green River, Wyoming and Ogden, Utah.  Here even the Challenger couldn’t negotiate those grades on its own.  These trains required double-heading.  Two Challengers with two crews (unlike lashing up diesels today where one crew operates multiple units from one cab).  And helper locomotives.  This took a lot of time.  And cost a lot of money.  So to negotiate these steep grades Union Pacific built the 4-8-8-4 articulated Big Boy.  Basically the Challenger on steroids.  The Big Boy could pull anything anywhere.  The Challenger and the Big Boy were the superstars of steam locomotives.  But these massive boilers on wheels required an enormous amount of maintenance.  Which is why they lasted but 20 years in service.  Replaced by tiny little diesel-electric locomotives.  That revolutionized railroading.  Because they were so less costly to maintain and operate.  Even if you had to use 7 of them to do what one Big Boy could do.



Tags: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

Triple Expansion Steam Engine

Posted by PITHOCRATES - November 6th, 2013

Technology 101

Pressure and Temperature have a Direct Relationship while Pressure and Volume have an Inverse Relationship

For much of human existence we used our own muscles to push things.  Which limited the work we could do.  Early river transport were barges of low capacity that we pushed along with a pole.  We’d stand on the barge and place the pole into the water and into the river bed.  Then push the pole away from us.  To get the boat to move in the other direction.

In more developed areas we may have cleared a pathway alongside the river.  And pulled our boats with animal power.  Of course, none of this helped us cross an ocean.  Only sail did that.  Where we captured the wind in sails.  And the wind pushed our ships across the oceans.  Then we started to understand our environment more.  And noticed relationships between physical properties.  Such as the ideal gas law equation:

Pressure = (n X R X Temperature)/Volume

In a gas pressure is determined my multiplying together ‘n’ and ‘R’ and temperature then dividing this number by volume.  Where ‘n’ is the amount of moles of the gas.  And ‘R’ is the constant 8.3145 m3·Pa/(mol·K).  For our purposes you can ignore ‘n’ and ‘R’.  It’s the relationship between pressure, temperature and volume that we want to focus on.  Which we can see in the ideal gas law equation.  Pressure and temperature have a direct relationship.  That is, if one rises so does the other.  If one falls so does the other.  While pressure and volume have an inverse relationship.  If volume decreases pressure increases.  If volume increases pressure decreases.  These properties prove to be very useful.  Especially if we want to push things.

Once the Piston traveled its Full Stroke on a Locomotive the Spent Steam vented into the Atmosphere 

So what gas can produce a high pressure that we can make relatively easy?  Steam.  Which we can make simply by boiling water.  And if we can harness this steam in a fixed vessel the pressure will rise to become strong enough to push things for us.  Operating a boiler was a risky profession, though.  As a lot of boiler operators died when the steam they were producing rose beyond safe levels.  Causing the boiler to explode like a bomb.

Early locomotives would burn coal or wood to boil water into steam.  The steam pressure was so great that it would push a piston while at the same time moving a connecting rod connected to the locomotive’s wheel.  Once the piston traveled its full stroke the spent steam vented into the atmosphere.  Allowing the pressure of that steam to dissipate safely into the air.  Of course doing this required the locomotive to stop at water towers along the way to keep taking on fresh water to boil into steam. 

Not all steam engines vented their used steam (after it expanded and gave up its energy) into the atmosphere.  Most condensed the low-pressure, low-temperature steam back into water.  Piping it (i.e., the condensate) back to the boiler to boil again into steam.  By recycling the used steam back into water eliminated the need to have water available to feed into the boiler.  Reducing non-revenue weight in steam ships.  And making more room available for fuel to travel greater distances.  Or to carry more revenue-producing cargo.

The Triple Expansion Steam Engine reduced the Expansion and Temperature Drop in each Cylinder

Pressure pushes the pistons in the steam engine.  And by the ideal gas law equation we see that the higher the temperature the higher the pressure.  As well as the corollary.  The lower the temperature the lower the pressure.  And one other thing.  As the volume increases the temperature falls.  So as the pressure in the steam pushes the piston the volume inside the cylinder increases.  Which lowers the temperature of the steam.  And the temperature of the piston and cylinder walls.  So when fresh steam from the boiler flows into this cylinder the cooler temperature of the piston and cylinder walls will cool the temperature of the steam.  Condensing some of it.  Reducing the pressure of the steam.  Which will push the piston with less force.  Reducing the efficiency of the engine.

There was a way to improve the efficiency of the steam engine.  By reducing the temperature drop during expansion (i.e., when it moves the piston).  They did this by raising the temperature of the steam.  And breaking down the expansion phase into multiple parts.  Such as in the triple expansion steam engine.  Where steam from the boiler entered the first cylinder.  Which is the smallest cylinder.  After it pushed the piston the spent steam still had a lot of energy in it looking to expand further.  Which it did in the second cylinder.  As the exhaust port of the first cylinder is piped into the intake port of the second cylinder.

The second cylinder is bigger than the first cylinder.  For the steam entering this cylinder is a lower-pressure and lower-temperature steam than that entering the first cylinder.  And needs a larger area to push against to match the down-stroke force on the first piston.  After it pushes this piston there is still energy left in that steam looking to expand.  Which it did in the third and largest cylinder.  After it pushed the third piston this low-pressure and low-temperature steam flowed into the condenser.  Where cooling removed what energy (i.e., temperature above the boiling point of water) was left in it.  Turning it back into water again.  Which was then pumped back to the boiler.  To be boiled into steam again.

By restricting the amount of expansion in each cylinder the triple expansion steam engine reduced the amount the temperature fell in each cylinder.  Allowing more of the heat go into pushing the piston.  And less of it go into raising the temperature of the piston and cylinder walls.  Greatly increasing the efficiency of the engine.  Making it the dominant maritime engine during the era of steam.



Tags: , , , , , , , , , , , , , , , , , , ,

Heat Transfer, Conduction, Convection, Radiation and Microwave Cooking

Posted by PITHOCRATES - September 4th, 2013

Technology 101

At the Atomic Level Vibrating Atoms create Heat

We make life comfortable and livable by transferring heat.  And by preventing the transfer of heat.  In fact, once we discovered how to make fire our understanding of heat transfer began and led to the modern life we know today.

At the atomic level heat is energy.  Vibrating atoms.  With electrons swirling around and jumping from one atom to another.  The more these atoms do this the hotter something is.  There is little atomic motion in ice.  And ice is very cold.  While there is a lot of motion in a pot of boiling water.  Which is why boiling water is very hot.

How do we get a pot of water to boil?  By transferring heat from a heat source.  A gas or electric burner.  This heat source is in contract with the pot.  The heat source agitates the atoms in the pot.  They begin to vibrate.  Causing the pot to heat up.  The water is in contact with the pot.  The agitated atoms in the pot agitate the atoms in the water.  Heating them up.  Giving us boiling water to cook with.  Or to make a winter’s day pleasant indoor.

Fin-Tube Heaters create a Rising Convection Current of Warm Air to Counter a Falling Cold Draft

If you touch a single-pane window in the winter in your house it feels very cold.  Cold outside air is in contact with the glass of the window.  Which slows the movement of the atoms.  Bringing the temperature down.  This cold temperature doesn’t conduct into the house.  The heat conducts out of the house.  Because there is no such thing as cold.  As cold is just the absence of heat.

The warm air inside the house comes in contact with the cold window.  Transferring heat from the air to the window.  The atoms in the air slow down.  The air cools down.  And falls.  This is the draft you feel at a closed window.  Cold air is heavier than warm air.  Which is why hot air rises.  And cold air falls.  As the cold air falls it pulls warmer air down in a draft.  Cooling it off.  Creating a convection current.

To keep buildings comfortable in the winter engineers design hot-water fin-tube heaters under each exterior window.  Gas burners heat up water piping inside a boiler.  The heat from the fire transfers heat to the boiler tubes.  Which transfers it to the water inside the tubes.  We then pump this heating hot water throughout the building.  As it enters a fin-tube heater under a window the hot water transfers heat to the heating hot water piping.  Attached to this piping are fins.  The heat transfers from the pipe to the fins.  Which heats the air in contact with these fins.  Hot air rises up and ‘washes’ the cold windows with warm air.  As it rises it pulls colder air up from the floor and through the heated fins.  Creating a convection current of warm air rising up to counter the falling cold draft.

Microwave Cooking won’t Sear Beef or Caramelize Onions like Conductive or Radiation Cooking

If you’ve ever waited for a ride outside an airport terminal on a cold winter’s day you’ve probably appreciated another type of heat transfer.  Radiation.  Outdoor curbside is open to the elements.  So you can’t heat the space.  Because there is no space.  Just a whole lot of outdoors.  But if you stand underneath a heater you feel toasty warm.  These are radiators.  A gas-fired or electric heating element that gets very, very hot.  So hot that energy radiates off of it.  Warming anything underneath it.  But if you step out from underneath you will feel cold.  It’s the same sitting around a campfire.  If you’re cold and wet you can sit by the fire and warm up in the fire’s radiation.  Move away from the fire, though, and you’re just cold and wet.

We use all these methods of heat transfer to cook our food.  Making life livable.  And enjoyable.  When we pan-fry we use conduction heating.  Transferring the heat from the burner to the pan to the food.  When we bake we use convection heating.  Transferring the heat from the burner to heat the air in the oven.  Which heats our food.  When we use the broiler we use radiation heating.  Using electric heating elements that glow red-hot, radiating energy into the food underneath them.  A convection oven adds a fan to an oven.  To blow heated air around our food.  Decreasing cooking time.

There’s one other cooking method.  One that is very common in many restaurants.  And in most homes.  But real chefs rarely use this method.  Microwaving.  With a microwave oven.  They’re great, convenient and fast but fine cooking isn’t about speed.  It’s about layering flavors and seasoning.  Which takes time.  Which you don’t get a lot of when a microwave begins vibrating the atoms in the water molecules in your food.   Which is how microwaves cook.  Cooking by vibrating atoms in your food brings temperatures up to serving temperatures.  Unlike conduction heating such as in pan-frying where we bring much higher temperatures into contact with our food.  Allowing us to sear beef and caramelize onions.  Something you can’t do in a microwave oven.  Which is why real chefs don’t use them.



Tags: , , , , , , , , , , , , , , , , , , , , , ,

Despite the Left’s Opposition to Fracking even the Environmental British are Joining In

Posted by PITHOCRATES - August 4th, 2013

Week in Review

One of the reasons the government tells us we must ‘invest’ in clean energy is to wean us off of costly foreign oil.  To give us energy independence.  And so we stop sending out money to nations in the world who don’t much care for us.  That’s why we must spend enormous amounts of tax dollars on things like solar and wind power.  Because we need them.  But because they are such poor business models they can’t operate without government subsidies.  So is there another option to give us that energy independence?  That doesn’t require government subsidies?  While even lowering our energy costs?  Yes there is.  And the British are now trying to play catch up to the United States (see The potential prize from fracking is huge by Michael Fallon posted 7/31/2013 on The Telegraph).

North, south, east and west, shale gas represents an exciting new potential resource for Britain that could contribute to our energy security, growth and jobs.

We only have to look across the Atlantic to see how it has reinvigorated the US economy: gas prices have halved, cutting costs for industry and consumers, and creating thousands of jobs and billions in new investment. Countries from India to Australia have looked on in envy at this boom – and are now joining in.

For its part, this Government is serious about shale. We are encouraging industry to find out how much is recoverable in all parts of the country. Given increasingly volatile international gas and oil prices, and our commitment to helping hard-pressed families with their bills, it would be irresponsible to ignore a new energy source right underneath our feet…

…residents understandably want reassurances that their water will not be contaminated. The facts are that around 2.5 million wells have now been fracked worldwide, more than 27,000 of them in the US in 2011. There is no evidence from America of fracking causing any groundwater contamination.

Other than in Hollywood movies.  And on television shows.  There it’s contaminating groundwater like there’s no tomorrow.  But with all that fracking going on in the United States the news is surprisingly barren of contaminated groundwater reports.  And you know they’d be leading all the news programs if there were.  Because the left hates fracking.  And the mainstream media leans left.  Way left.

That energy boom is a private boom.  It’s not because of the government.  It’s in spite of the government.  Who has launched a war on coal and oil.  Shutting down oil production on the Gulf of Mexico.  And on all federal lands.  Or making it very difficult for those who try.

Much of the global warming nonsense came from the University of East Anglia.  Making Britain near ground zero in the battle against global warming.  And here they are.  Wanting to frack to bring energy costs down for households.  Create jobs.  And reduce dependency on foreign oil.  Pity the United States government doesn’t care enough about the American people to do the same.



Tags: , , , , , , , , , , , , , , ,

« Previous Entries