Engine Block Heaters and Battery Heaters

Posted by PITHOCRATES - February 19th, 2014

Technology 101

As Matter loses Heat it shrinks from a Gas to a Liquid to a Solid

There is no such thing as cold.  Cold is simply the absence of heat.  Which is a real thing.  Heat.  It’s a form of energy.  Warm things have a lot of energy.  Cold things have less energy.  The Kelvin scale is a measurement of temperature.  Like degrees used when measuring temperature in Celsius or Fahrenheit.  Where 32 degrees Fahrenheit equals 0 degrees Celsius.  And 0 degrees Celsius equals 273.15 kelvin.  Not ‘degrees’ kelvin.  Just kelvin.

When something cools it loses heat energy.  The molecular activity slows down.  Steam has a lot of molecular activity.  At 212 degrees Fahrenheit (100 degrees Celsius or 373.15 kelvin) the molecular activity decreases enough (i.e., loses energy) that steam changes to water.  At 32 degrees Fahrenheit (0 degrees Celsius or 273.15 kelvin) the molecular activity decreases enough (i.e., loses energy) that water turns into ice.

The more heat matter loses the less molecules move around.  At absolute zero (0 kelvin) there is no heat at all.  And no molecular movement.  Making 0 kelvin the ‘coldest’ anything can be.  For 0 kelvin represents the absence of all heat.  As matter loses heat it shrinks.  Gases become liquid.  And liquids becomes solid.  (Water, however, is an exception to that rule.  When water turns into ice it expands.  And cracks our roadways.)  They become less fluid.  Or more viscous.  Cold butter is harder to spread on a roll than warm butter.  Because warm butter has more heat energy than cold butter.  So warm butter is less viscous than cold butter.

Vehicles in Sub-Freezing Temperatures can Start Easily if Equipped with an Engine Block Heater

In a car’s internal combustion engine an air-fuel mixture enters the cylinder.  As the piston comes up it compresses this mixture.  And raises its temperature.  When the piston reaches the top the air-fuel mixture is at its maximum pressure and temperature.  The spark plug then provides an ignition source to cause combustion.  (A diesel engine operates at such a high compression that the temperature rise is so great the air-fuel mixture will combust without an ignition source).  Driving the piston down and creating rotational energy via the crank shaft.

For this to happen a lot of things have to work together.  You need energy to spin the engine before the combustion process.  You need lubrication to allow the engine components to move without causing wear and tear.  And you need the air-fuel mixture to reach a temperature to burn cleanly and to extract as much energy from combustion as possible.  None of which works well in very cold temperatures.

Vehicles operating in sub-freezing temperatures need a little help.  Manufacturers equip many vehicles sold for these regions with engine block heaters.  These are heating elements in the engine core.  You’ll know a vehicle has one when you see an electrical cord coming out of the engine compartment.  When these engines aren’t running they ‘plug in’ to an electrical outlet.  A timer will cycle these heaters on and off.  Keeping the engine block warmer than the subfreezing temperatures.

The Internal Combustion Engine is Ideal for use in Cold Temperatures

At subfreezing temperatures engine oil because more viscous.  And more like tar.  This does not flow well through the engine.  So until it warms up the engine operates basically without any lubrication.  In ‘normal’ temperatures the oil heats up quickly and flows through the engine before there’s any damage.  At subfreezing temperatures oil needs a little help when starting.  So the oil sump is heated.  Like an engine block heater.  So when someone tries to start the engine the oil is more like oil and less like tar.

Of course, for any of this to help start an engine you have to be able to turn the engine over first.  And to do that you need a charged battery.  But even a charged battery needs help in sub-freezing temperatures.  For in these temperatures there is little molecular action in the battery.  And without molecular activity there will be little current available to power the engine’s starter.  So there are heaters for batteries, too.  Electric blankets or pads that sit under or wrap around a battery.  To warm the battery to let the chemicals inside move around more freely.  So they can produce the electric power it needs to turn an engine over on a cold day.

Once an engine block, the engine oil and battery are sufficiently warmed by external electric power the engine can start.  Once it warms up it can operate like it can at less frigid temperatures.  The engine alternator powers the electrical systems on the vehicle.  And recharges the battery.  The engine coolant heats up and provides heat for the passenger compartment.  And defrosts the windows.  Once the engine is warm it can shut down and start again an hour or so later with ease.  Making it ideal for use in cold temperatures.  Unlike an electric car.  For the colder it gets the less energy its batteries will have.  Making it a risky endeavor to drive to the store in the Midwest or the Northeast during a winter such as this.  Something people should think about before buying an all-electric car.



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Carbon, Carbon Cycle, Crude Oil, Petroleum, Hydrocarbons, Oil Refinery, Cracking, Sweet Crude, Sour Crude, Gasoline and Diesel Engines

Posted by PITHOCRATES - April 25th, 2012

Technology 101

Crude Oil is made from Long Chains of Carbon Atoms Bonded Together with a lot of Hydrogen Atoms Attached Along the Way

Carbon.  It’s everywhere.  And in everything.  Like all matter it cannot be created.  Or destroyed.  It just changes.  As it creates the circle of life.  The carbon cycle.  Plants and trees absorb carbon out of the atmosphere.  And converts it into biomass.  Into wood.  And into animal food.  Where the digestive system converts it into carbon-based living flesh and blood.  That exhales carbon.  Plants absorb carbon and release oxygen.  Plants can’t grow without carbon.  And we can’t breathe without plants growing.  Carbon is constantly changing.  But never created.  Or destroyed.  From diamonds to pencils.  From sugar to carbonated soda.  From plastics to human beings.  It’s everywhere.  And everything.  Why, it’s life itself.

Carbon is a time traveler.  Carbon that once traveled through the atmosphere disappeared millions of years ago.  Buried underneath the surface of the earth.  Under intense heat and pressure.  Plankton and algae and other biomasses decayed until there was almost nothing left but carbon atoms.  Long chains of carbon atoms.  Forming great, restless pools of black goo beneath the surface.   Waiting for the modern world to arrive.  Waiting for the internal combustion engine.  The jet engine.  And plastics.  When they could be reborn.  And see the light of day again.

Crude oil.  Petroleum.  Black gold.  Texas tea.  Hydrocarbons.  Long chains of carbon atoms bonded together with a lot of hydrogen atoms attached along the way.  In the ground they’re mostly long chains.  When we get them above ground we can break those chains into different lengths.  And create many different things.  C16H34 (hexadecane).  C9H20 (nonane).  C8H18 (octane).  C7H16 (heptane).  C5H12 (pentane).  C4H10 (butane).  C6H6 (benzene).  CH4 (methane).  Some of these you may be familiar with.  Some you may not.  Methane is a flammable gas.  Hydrocarbon chains from pentane to octane make gasoline.  Hydrocarbon chains from nonane to hexadecane make diesel fuel, kerosene and jet fuel.  Chains with more carbon atoms make lubricants.  Chains with even more carbon atoms make asphalt.  While chains with 4 carbon atoms or less make gases.  All these things made from the same black goo.  A true marvel of Mother Nature.  Or God.  Depending on your inclination.

Older Coastal Refineries make more Expensive Gasoline than the Newer Refineries due to the Availability of Sweet versus Sour Crude

Another great carbon-based product it bourbon.  Made from a corn sour mash.  We heat this and the alcohol in it boils off.  That is, we distill it.  We run this gas through a coiling coil and it condenses back into a liquid.  And after a few more steps we get delicious bourbon whiskey.  Distilleries give tours.  If you get a chance you should take one.  You won’t get to sample any of the distilled spirits (insurance reasons).  But you will get a feel for what an oil refinery is.

An oil refinery works on the same principles.  Boil and condense.  And cracking.  Cracking those long hydrocarbon chains apart into all those different chains.  Long and small.  Into liquids and gases.  Even solid lubricants and asphalt.  All made possible because of their different boiling points.  The gases having lower boiling points.  The solids having higher boiling points.  And the liquids having boiling points somewhere in between.

Refineries are complex processing plants.  Not only because of all those different hydrocarbon chains.  But because of the crude oil introduced to these plants.  For there is light sweet crude.  And heavier sour crude.  The difference being the additional stuff that we need to remove.  Such as sulfur.  An environmental problem.  So we have to remove as much of it as possible during the refining process to meet EPA standards.  The sweet crudes are lower in sulfur.  Making them the crude of choice.  But this has also been the most popular crude through the years.  So its resources are dwindling.  Making it more expensive.  As are all the products refined from it.  Especially gasoline.  The more sour crudes have higher sulfur content.  And require more refining steps to remove that sulfur.  Which means additional refinery equipment.  So the older refineries that were refining the light sweet crude can’t refine the heavier sour crudes.  Which is why the refineries along the coasts make more expensive gasoline than the newer ones in the interior refining the heavier sour crudes.  Due to the availability of sweet crude versus sour crude.

The Modern World is brought to us by a Complex Economy which is brought to us by Petroleum

One of the main uses of refined crude oil is fuel for internal combustion engines.  In particular, gasoline engines and diesel engines.  Which are very similar.  The difference being the mode of ignition.  And, of course, the fuel.  Gasoline engines compress an air-fuel mixture in the cylinder.  At the top of the compression stroke a spark plug ignites this highly compressed and heated mixture.  Sending the piston down.  If the combustion occurs too early it could place undo stresses on the piston connecting rods and the crank shaft.  By trying to send the piston down when it was coming up.  Causing a knocking sound.  Which is a bad sound to hear.  And if you hear it you should probably make sure you’re using the right gasoline.  If you are you need to have you car serviced.  Because continued knocking may break something.  And if it does your engine will work no more.  So this is where octane comes in the blending of gasoline.  It’s expensive.  But the more of it in gasoline the higher the compression you can have.  And the less knocking.  Which is its only purpose.  It doesn’t give you any more power.  The higher compression does.  Which the higher octane allows.  Using the higher octane gas in a standard compression engine won’t do anything but waste your hard earned money.

And speaking of higher compression engines, that brings us to diesel engines.  Which are similar to gasoline engines only they operate under a higher compression.  And don’t use spark plugs.  These engines compress air only.  Which allows the higher compression without pre-ignition.  At the top of their compression stroke a fuel injector squirts diesel fuel into the hot compressed air where it combusts on contact.  Diesel fuel has a higher energy content than gasoline.  Meaning for the same volume of fuel diesel can take you further than gasoline.  Which is why trucks, locomotives and ships use diesel.  But diesel tends to pollute more.  The smell and the soot kept diesel out of our cars for a long time.  As well as the difficulty of starting in cold climates.  Advanced computer controlled systems have helped, though, and we’re seeing more diesel used in cars now.

The modern world is brought to us by a complex economy.  Where goods and raw materials traverse the globe.  To feed our industries.  And to ship our finished goods.  Which we put on trucks, trains, ships and airplanes.  None of which would be possible without a portable, stable, energy-dense fuel.  That only refined petroleum can give us.  It’s better than animal power.  Water power.  Wind power.  Or steam power.  For there is nothing that we can use in our trucks, trains, ships and airplanes other than refined petroleum products today that wouldn’t be a step backwards in our modern world.  Nothing.  Making petroleum truly a marvel of Mother Nature.  Or God.  Depending on your inclination.



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