Fun Learning: HORSEPOWER
Thread Starter
A Philanthropical Fruit
Joined: Sep 2004
Posts: 756
Likes: 0
From: Ann Arbor Michigan Aim: nickbeier
Fun Learning: HORSEPOWER
I always found it fun to learn about car engines and such. When persented with the oppertunity to write a paper on a freelance chemistry topic, and present the info to my class, I got excited!
Here is the begining of my paper, I'd be happy to get advice as I go along. It starts off with a boring intro and basic background info. I plan on getting to turbos and nitrous on page 2
EDIT: PAPER NOW DONE! Suggestions still needed, it's not due till monday
Nick Beier
The Internal Combustion Engine is a part of our daily lives. We use them often to mow our lawns, generate electricity, and most commonly to drive to school everyday. This way of producing power is largely used, but greatly underappreciated. The mechanics and chemistry behind the inner workings of these engines is quite fascinating.
Increasing the output of an Internal Combustion Engine requires much thought and is often a key part in designing the engine. The original design of most automotive engines is very interesting, but more so are the possibilities of modifying one. To take upon oneself the task of increasing the horsepower of his engine is quite the adventure, and will be the main focus of this paper.
To understand how to optimize the output (or in some cases insanely increase the output) of an Internal Combustion Engine, one must first have a thorough understanding of how it works. As the name implies, the engine produces power by combusting fuel inside a closed container and harnessing the energy released. This reaction takes place in a cylinder which is compressed by a piston: the combustion occurs, and the piston is forced down, converting chemical energy into kinetic energy.
This process is most commonly done in a four stroke combustion cycle. The process involves four stages (or four strokes): Intake, Compression, Combustion, and Exhaust. Stoichiometric amounts of oxygen and fuel are drawn into the cylinder through intake valves, compressed by the piston, ignited and then combust - pushing the piston down with great force. The remains are pushed out of the cylinder through exhaust valves, and the process begins again with the intake stroke. (cite Howstuff)
The energy is released in this process in the 3rd stroke: Combustion. When the fuel and air mixture is ignited, it follows a standard combustion reaction:
C7H14 + O2 CO2 + H2O + Energy
The reaction that takes place in the cylinder has only Carbon Dioxide and water (both in gaseous form) as products, along with copious amounts of energy. So much energy, in fact, that the combustion stroke provides power for the other three strokes, the activation energy for following combustions, and enough kinetic energy to make speed freaks worship the ways of chemistry after hitting 100mph in under ten seconds! In some common vehicle applications, this single reaction can take place almost 15,000 times a minute. (cite the first one)
To increase the power of these engines, many methods can be used. Increasing the volume of the combustion chamber (the displacement), using a more powerful fuel, or just adding more cylinders are all plausible routes. All these are variables to be considered in the designing the engine, but how can one modify one? Assuming that changing the displacement or adding more cylinders would be too expensive, and a fuel more powerful than gasoline would be illegal, we are left with few options. The most common route in increasing the output of an engine lies in the combustion stroke.
The combustion stroke is powered by the oxygen and fuel that react in the cylinder. The most effective way to gain more power, then, would be to increase the amount of oxygen and fuel combusting. For instance, one could double the amount of reactants, and intern double the amount of products by doing so. Since energy is a “product” of the reaction, it follows that we could obtain twice the amount of energy from twice the reactants. With this principle in mind, increasing the amount of oxygen and fuel in each cylinder would increase our power output proportionally. Since a car can control the amount of fuel flowing to each cylinder, our goal will then be to gather as much oxygen as possible into each cylinder.
Have you ever noticed that a car runs faster on a cold evening? This is one of the easiest ways of increasing the amount of reactants in each cylinder, cooling the intake air. Colder air is denser, meaning more molecules per unit volume. The same volume of cold air therefore contains more molecules of oxygen than hotter air does. Running your car on a cold night (or somehow cooling the intake air) increases the amount of oxygen in our cylinders, and therefore increases the energy output of each combustion.
The first modification we will examine, a Cold Air Intake, was designed with that concept in mind. Being on the most simple and inexpensive modifications one can do, a cold air intake is just a tube with a filter on the end. This tube draws air from a colder place than would a normal air intake (typically from outside of the car), resulting in denser intake air, more oxygen per unit volume, and more power.
A much more interesting and elaborate modification is the Turbocharger. A turbocharger is a type of forced induction system. These work on the basis of compressing the air before it reaches each cylinder. As the term forced induction implies, a turbocharger literally crams extra air into the intake manifold. Theoretically, if one could force twice as much air into an engine as it would normally have, he could create twice the amount of power from the engine! In this way, a turbocharger is extremely effective. (cite howstuff)
A turbocharger mechanically works by utilizing the exhaust gases of an engine to spin a turbine, which powers a pump that compresses the intake air. Compressing the intake air (along with the close proximity of hot exhaust gases) makes the air very hot, however. Hot air, as we learned, doesn’t contain as much oxygen as the same volume of cold air. To fix this problem, an Intercooler is used.
An intercooler passes the hot intake air from the turbocharger through a series of little tubes with much surface area. An intercooler is typically mounted on the front of a car, exposed to the cold air rushing by at high speeds. Outside air surrounds these little tubes, cooling them down, and cooling the intake air inside of them. An intercooler spray can also be used, which sprays water on these little tubes. The water quickly evaporates (and endothermic process), cooling the tubes further. Cooling the intercooler tubes is all in effort to decrease the temperature of the intake air, allowing more oxygen to enter the engine.
A full forced induction system (with a turbo charger and intercooler) uses both methods of bringing more oxygen to the engine: Forcing it in, and cooling it down.
Nitrous Oxide is another modification that uses these same two principles. It can also be considered a forced induction system, but is far different than any turbocharger or intercooler. The magic of nitrous oxide lies in the chemistry behind it. There is no big turbine or pump, just a tank of this magic compound. Nitrous Oxide (N2O) is colorless and non-flammable gas typically used for medical purposes as “laughing gas”. It exists as a gas at room temperature, and as a liquid (when under extreme pressure) in the bottle.
Nitrous Oxide is typically injected into the intake air of an engine. Before it even reaches the cylinders, the first bit of chemical magic occurs. Nitrous Oxide is a liquid in the bottle and a gas while in the intake air. This phase change from a liquid to a gaseous state is an endothermic process and absorbs large amounts of heat, resulting in a 65 to 75°F drop in intake air temperatures (cite SCC). This cooling alone accomplishes more than would most cold air intakes or intercoolers.
A special characteristic of Nitrous Oxide is that at 565°F, it decomposes into nitrogen and oxygen: N2O N2 + ˝O2
During the compression stroke of a four stroke engine, the increase in pressure causes temperatures to rise to about 565°F, causing this decomposition to occur. The secret behind nitrous oxide is that is releases extra oxygen in each cylinder, providing for much more combustion. As stated by Hib Halverson,
Nitrous oxide has this effect because it has a higher percentage of oxygen content than does the air in the atmosphere. Nitrous has 36% oxygen by weight and the atmosphere has 23%. Additionally, nitrous oxide is 50% more dense than air at the same pressure. Thus, a cubic foot of nitrous oxide contains 2.3 times as much oxygen as a cubic foot of air. Just do a bit of math in your head and you can see if we substitute some nitrous oxide for some of the air going into an engine than add the appropriate amount of additional fuel, the engine is going to put out more power.
(cite last one)
In this way, Nitrous Oxide works as a forced induction system similar to a turbo charger: it brings extra oxygen to each cylinder along with cooling the intake air “using the miracle of chemistry instead of a mechanical compressor” (cite SCC).
Cite these:
http://www.k12.nf.ca/janecollins/tea...rous_oxide.htm
http://auto.howstuffworks.com/engine14.htm
http://auto.howstuffworks.com/framed...ib/nitrous.htm
sport compact car
Here is the begining of my paper, I'd be happy to get advice as I go along. It starts off with a boring intro and basic background info. I plan on getting to turbos and nitrous on page 2
EDIT: PAPER NOW DONE! Suggestions still needed, it's not due till monday
Nick Beier
Increasing the performance of Internal Combustion Engines
The Internal Combustion Engine is a part of our daily lives. We use them often to mow our lawns, generate electricity, and most commonly to drive to school everyday. This way of producing power is largely used, but greatly underappreciated. The mechanics and chemistry behind the inner workings of these engines is quite fascinating.
Increasing the output of an Internal Combustion Engine requires much thought and is often a key part in designing the engine. The original design of most automotive engines is very interesting, but more so are the possibilities of modifying one. To take upon oneself the task of increasing the horsepower of his engine is quite the adventure, and will be the main focus of this paper.
To understand how to optimize the output (or in some cases insanely increase the output) of an Internal Combustion Engine, one must first have a thorough understanding of how it works. As the name implies, the engine produces power by combusting fuel inside a closed container and harnessing the energy released. This reaction takes place in a cylinder which is compressed by a piston: the combustion occurs, and the piston is forced down, converting chemical energy into kinetic energy.
This process is most commonly done in a four stroke combustion cycle. The process involves four stages (or four strokes): Intake, Compression, Combustion, and Exhaust. Stoichiometric amounts of oxygen and fuel are drawn into the cylinder through intake valves, compressed by the piston, ignited and then combust - pushing the piston down with great force. The remains are pushed out of the cylinder through exhaust valves, and the process begins again with the intake stroke. (cite Howstuff)
The energy is released in this process in the 3rd stroke: Combustion. When the fuel and air mixture is ignited, it follows a standard combustion reaction:
C7H14 + O2 CO2 + H2O + Energy
The reaction that takes place in the cylinder has only Carbon Dioxide and water (both in gaseous form) as products, along with copious amounts of energy. So much energy, in fact, that the combustion stroke provides power for the other three strokes, the activation energy for following combustions, and enough kinetic energy to make speed freaks worship the ways of chemistry after hitting 100mph in under ten seconds! In some common vehicle applications, this single reaction can take place almost 15,000 times a minute. (cite the first one)
To increase the power of these engines, many methods can be used. Increasing the volume of the combustion chamber (the displacement), using a more powerful fuel, or just adding more cylinders are all plausible routes. All these are variables to be considered in the designing the engine, but how can one modify one? Assuming that changing the displacement or adding more cylinders would be too expensive, and a fuel more powerful than gasoline would be illegal, we are left with few options. The most common route in increasing the output of an engine lies in the combustion stroke.
The combustion stroke is powered by the oxygen and fuel that react in the cylinder. The most effective way to gain more power, then, would be to increase the amount of oxygen and fuel combusting. For instance, one could double the amount of reactants, and intern double the amount of products by doing so. Since energy is a “product” of the reaction, it follows that we could obtain twice the amount of energy from twice the reactants. With this principle in mind, increasing the amount of oxygen and fuel in each cylinder would increase our power output proportionally. Since a car can control the amount of fuel flowing to each cylinder, our goal will then be to gather as much oxygen as possible into each cylinder.
Have you ever noticed that a car runs faster on a cold evening? This is one of the easiest ways of increasing the amount of reactants in each cylinder, cooling the intake air. Colder air is denser, meaning more molecules per unit volume. The same volume of cold air therefore contains more molecules of oxygen than hotter air does. Running your car on a cold night (or somehow cooling the intake air) increases the amount of oxygen in our cylinders, and therefore increases the energy output of each combustion.
The first modification we will examine, a Cold Air Intake, was designed with that concept in mind. Being on the most simple and inexpensive modifications one can do, a cold air intake is just a tube with a filter on the end. This tube draws air from a colder place than would a normal air intake (typically from outside of the car), resulting in denser intake air, more oxygen per unit volume, and more power.
A much more interesting and elaborate modification is the Turbocharger. A turbocharger is a type of forced induction system. These work on the basis of compressing the air before it reaches each cylinder. As the term forced induction implies, a turbocharger literally crams extra air into the intake manifold. Theoretically, if one could force twice as much air into an engine as it would normally have, he could create twice the amount of power from the engine! In this way, a turbocharger is extremely effective. (cite howstuff)
A turbocharger mechanically works by utilizing the exhaust gases of an engine to spin a turbine, which powers a pump that compresses the intake air. Compressing the intake air (along with the close proximity of hot exhaust gases) makes the air very hot, however. Hot air, as we learned, doesn’t contain as much oxygen as the same volume of cold air. To fix this problem, an Intercooler is used.
An intercooler passes the hot intake air from the turbocharger through a series of little tubes with much surface area. An intercooler is typically mounted on the front of a car, exposed to the cold air rushing by at high speeds. Outside air surrounds these little tubes, cooling them down, and cooling the intake air inside of them. An intercooler spray can also be used, which sprays water on these little tubes. The water quickly evaporates (and endothermic process), cooling the tubes further. Cooling the intercooler tubes is all in effort to decrease the temperature of the intake air, allowing more oxygen to enter the engine.
A full forced induction system (with a turbo charger and intercooler) uses both methods of bringing more oxygen to the engine: Forcing it in, and cooling it down.
Nitrous Oxide is another modification that uses these same two principles. It can also be considered a forced induction system, but is far different than any turbocharger or intercooler. The magic of nitrous oxide lies in the chemistry behind it. There is no big turbine or pump, just a tank of this magic compound. Nitrous Oxide (N2O) is colorless and non-flammable gas typically used for medical purposes as “laughing gas”. It exists as a gas at room temperature, and as a liquid (when under extreme pressure) in the bottle.
Nitrous Oxide is typically injected into the intake air of an engine. Before it even reaches the cylinders, the first bit of chemical magic occurs. Nitrous Oxide is a liquid in the bottle and a gas while in the intake air. This phase change from a liquid to a gaseous state is an endothermic process and absorbs large amounts of heat, resulting in a 65 to 75°F drop in intake air temperatures (cite SCC). This cooling alone accomplishes more than would most cold air intakes or intercoolers.
A special characteristic of Nitrous Oxide is that at 565°F, it decomposes into nitrogen and oxygen: N2O N2 + ˝O2
During the compression stroke of a four stroke engine, the increase in pressure causes temperatures to rise to about 565°F, causing this decomposition to occur. The secret behind nitrous oxide is that is releases extra oxygen in each cylinder, providing for much more combustion. As stated by Hib Halverson,
Nitrous oxide has this effect because it has a higher percentage of oxygen content than does the air in the atmosphere. Nitrous has 36% oxygen by weight and the atmosphere has 23%. Additionally, nitrous oxide is 50% more dense than air at the same pressure. Thus, a cubic foot of nitrous oxide contains 2.3 times as much oxygen as a cubic foot of air. Just do a bit of math in your head and you can see if we substitute some nitrous oxide for some of the air going into an engine than add the appropriate amount of additional fuel, the engine is going to put out more power.
(cite last one)
In this way, Nitrous Oxide works as a forced induction system similar to a turbo charger: it brings extra oxygen to each cylinder along with cooling the intake air “using the miracle of chemistry instead of a mechanical compressor” (cite SCC).
Cite these:
http://www.k12.nf.ca/janecollins/tea...rous_oxide.htm
http://auto.howstuffworks.com/engine14.htm
http://auto.howstuffworks.com/framed...ib/nitrous.htm
sport compact car
Senior Member
Joined: Jun 2003
Posts: 4,703
Likes: 0
From: Eastern MA
and most commonly to drive to school everyday.
Good topic too, I wish I had that subject to write about in any class.
Thread Starter
A Philanthropical Fruit
Joined: Sep 2004
Posts: 756
Likes: 0
From: Ann Arbor Michigan Aim: nickbeier
This process is most commonly done in a four stroke combustion cycle. The process involves four stages (or four strokes): Intake, Compression, Combustion, and Exhaust. Stoichiometric amounts of air and fuel are drawn into the cylinder through intake valves, compressed by the piston, ignited and then combust - pushing the piston down with great force. The remains are pushed out of the cylinder through exhaust valves, and the process begins again with the intake stroke. (cite Howstuff)
The energy is released in this process in the 3rd stroke: Combustion. When the fuel and air mixture is ignited, it follows a standard combustion reaction:
C7H14 + O2 CO2 + H2O + Energy
The reaction that takes place in the cylinder has only Carbon Dioxide and water (both in gaseous form) as products, along with copious amounts of energy. So much energy, in fact, that the combustion stroke provides power for the other three strokes, the activation energy for following combustions, and enough kinetic energy to make speed freaks worship the ways of chemistry after hitting 100mph in under ten seconds!
The energy is released in this process in the 3rd stroke: Combustion. When the fuel and air mixture is ignited, it follows a standard combustion reaction:
C7H14 + O2 CO2 + H2O + Energy
The reaction that takes place in the cylinder has only Carbon Dioxide and water (both in gaseous form) as products, along with copious amounts of energy. So much energy, in fact, that the combustion stroke provides power for the other three strokes, the activation energy for following combustions, and enough kinetic energy to make speed freaks worship the ways of chemistry after hitting 100mph in under ten seconds!
Thread Starter
A Philanthropical Fruit
Joined: Sep 2004
Posts: 756
Likes: 0
From: Ann Arbor Michigan Aim: nickbeier
[con't from last paragraph]In some common vehicle applications, this single reaction can take place almost 30,000 times a minute.
To increase the power of these engines, many methods can be used. Increasing the volume of the combustion chamber (the displacement), using a more powerful fuel, or just adding more cylinders are all plausible routes. All these are variables to be considered in the designing the engine, but how can one modify one? Assuming that changing the displacement or adding more cylinders would be too expensive, and a fuel more powerful than gasoline would be illegal, we are left with few options. The most common route in increasing the output of an engine lies in the combustion stroke.
The combustion stroke is powered by the air and fuel that react in the cylinder. The most effective way to gain more power, then, would be to increase the amount of air and fuel combusting. For instance, one could double the amount of reactants, and intern double the amount of products by doing so. Since energy is a “product” of the reaction, it follows that we could obtain twice the amount of energy from twice the reactants. With this principle in mind, increasing the amount of air and fuel in each cylinder would increase our output proportionally. [remove this next sentence:] This concept is called Forced Induction; simply described as cramming more reactants into each cylinder.
EDIT: Hmmm I'll get to forced induction later, on second thought. Next paragrah should focus on colder air being more dense, which isn't forced induction. I'll introduce that term soon though
To increase the power of these engines, many methods can be used. Increasing the volume of the combustion chamber (the displacement), using a more powerful fuel, or just adding more cylinders are all plausible routes. All these are variables to be considered in the designing the engine, but how can one modify one? Assuming that changing the displacement or adding more cylinders would be too expensive, and a fuel more powerful than gasoline would be illegal, we are left with few options. The most common route in increasing the output of an engine lies in the combustion stroke.
The combustion stroke is powered by the air and fuel that react in the cylinder. The most effective way to gain more power, then, would be to increase the amount of air and fuel combusting. For instance, one could double the amount of reactants, and intern double the amount of products by doing so. Since energy is a “product” of the reaction, it follows that we could obtain twice the amount of energy from twice the reactants. With this principle in mind, increasing the amount of air and fuel in each cylinder would increase our output proportionally. [remove this next sentence:] This concept is called Forced Induction; simply described as cramming more reactants into each cylinder.
EDIT: Hmmm I'll get to forced induction later, on second thought. Next paragrah should focus on colder air being more dense, which isn't forced induction. I'll introduce that term soon though
Push to shock!
Joined: Sep 2002
Posts: 4,583
Likes: 0
From: Palo Alto, CA
Originally Posted by beier
C7H14 + O2 CO2 + H2O + Energy
Originally Posted by beier
The reaction that takes place in the cylinder has only Carbon Dioxide and water (both in gaseous form) as products, along with copious amounts of energy
Thread Starter
A Philanthropical Fruit
Joined: Sep 2004
Posts: 756
Likes: 0
From: Ann Arbor Michigan Aim: nickbeier
(con't)
With this principle in mind, increasing the amount of oxygen and fuel in each cylinder would increase our power output proportionally. Since a car can control the amount of fuel flowing to each cylinder, our goal will then be to gather as much oxygen as possible into each cylinder.
Have you ever noticed that a car runs faster on a cold evening? This is one of the easiest ways of increasing the amount of reactants in each cylinder, cooling the intake air. Colder air is denser, meaning more molecules per unit volume. The same volume of cold air therefore contains more molecules of oxygen than hotter air does. Running your car on a cold night (or somehow cooling the intake air) increases the amount of oxygen in our cylinders, and therefore increases our energy output.
EDIT: I'm not sure about this concept. I know that denser air has more O2, but I think there's another effect of cold air having to do with pressure that effects the combustion. Could anybody inform me? I'll research this too.
I’ll continue this subject in this sequence:
-Cold air helps
-run car on a cold night
-CAI
-Force air in there
-turbo/super
-also use intercoolers to cool air
-Combine both: More oxygen and colder intake
-Nitrous!
With this principle in mind, increasing the amount of oxygen and fuel in each cylinder would increase our power output proportionally. Since a car can control the amount of fuel flowing to each cylinder, our goal will then be to gather as much oxygen as possible into each cylinder.
Have you ever noticed that a car runs faster on a cold evening? This is one of the easiest ways of increasing the amount of reactants in each cylinder, cooling the intake air. Colder air is denser, meaning more molecules per unit volume. The same volume of cold air therefore contains more molecules of oxygen than hotter air does. Running your car on a cold night (or somehow cooling the intake air) increases the amount of oxygen in our cylinders, and therefore increases our energy output.
EDIT: I'm not sure about this concept. I know that denser air has more O2, but I think there's another effect of cold air having to do with pressure that effects the combustion. Could anybody inform me? I'll research this too.
I’ll continue this subject in this sequence:
-Cold air helps
-run car on a cold night
-CAI
-Force air in there
-turbo/super
-also use intercoolers to cool air
-Combine both: More oxygen and colder intake
-Nitrous!
Thread Starter
A Philanthropical Fruit
Joined: Sep 2004
Posts: 756
Likes: 0
From: Ann Arbor Michigan Aim: nickbeier
Originally Posted by Kestrel
Cars burn iso-octane, not heptane (C8H18)
I don't know how detailed you want to get, but for sure combustion products are never just CO2 and H2O. For sure you will CO and NOx, and SOx or C depending on your fuel type and stoichiometry. And that's just brushing the surface...
I don't know how detailed you want to get, but for sure combustion products are never just CO2 and H2O. For sure you will CO and NOx, and SOx or C depending on your fuel type and stoichiometry. And that's just brushing the surface...
About the exhaust - I meant to say "in a perfect world". I'll add that phrase in when completing the final draft. Trying to keep concepts simple here.
Thanks for the reply
Push to shock!
Joined: Sep 2002
Posts: 4,583
Likes: 0
From: Palo Alto, CA
Originally Posted by beier
About the exhaust - I meant to say "in a perfect world". I'll add that phrase in when completing the final draft. Trying to keep concepts simple here.
If you have a lean mixture, you have excess oxygen, and if you have a rich mixture you have excess fuel.