Compression-Fired Engines

Since lead can poison auto exhaust catalysts, automobiles equipped with catalytic exhaust-control devices require lead-free gasoline, which has become the standard motor fuel. Sulfur in gasoline is also detrimental to catalyst performance, so sulfur levels in gasoline are kept very low. 

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Livengood and Wu (112) correlated rapid compression, motored and fired engine experiments on the assumption that a reaction entity was formed in all cases by the same kind of reaction, and that ignition occurred when the entity reached a critical concentration. 

If you want to experiment, then you must try the experiment under pressure with the pistons in motion. The compression in the cylinders is 165 to 180 psi. in each. The engine turns over 4 or 5 times before it starts. Repeated compression and the right amount of fire in the hole and it will work. 

Inside a gasoline engine the air and gas are compressed to somewhere between 85 psi and 180 psi in most engines. When the piston is just past TDC the plug fires and the gases explode as the carbon components superheat under pressure. 

Boyd, S., Compression Creep Rupture ofanE-Glass/Vinyl Ester Composite Subjected to Combined Mechanical and Fire Loading Conditions, Dissertation for Doctor of Philosophy in Engineering Mechanics, 2006. 

The mechanical actions consist of friction, striking and the sudden compression of the air. Humans have used these methods to obtain fire from ancient times, and they remain in the form of matches, lighters and in the ignition of some internal combustion engines. These principles of creating fire are quite important in pyrotechnics and are described here in some detail. 

The fire department is inspecting the fire extinguishers in the chemical engineering building. A No. 2 gas cylinder, weighing 52.27 lb when completely evacuated, is placed on an accurate scale and filled with compressed carbon dioxide gas. When the gas in the cylinder has reached room temperature (54.5°F), the pressure in the cylinder is measured and found to be 338 psig. The capacity of the cylinder is 2,04 fp. Use the van der Waals equation of state to estimate what the scale will read in lb. 

This is the power needed to overcome the friction, compression, and inertia of the engine to bring the engine rotation speed up sufficiently to fire the cylinders. The crank power will vary from engine to engine and with temperature, but it is generally in the kilowatt range. 

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