|Fig. 1: Illustration of original Lenoir engine.  (Public domain work.)|
Americas love of the internal combustion engine as the heart of her automobiles has led us down a one way road toward foreign oil dependency. America is one of the top crude oil producers in the world yet we still import massive amounts of fossil fuels.  With the huge investments into the infrastructure to support these vehicles we must find a way to continue to not only fuel them but also develop them. The electric vehicle may play a role in the future but it is a long way off from being a car that the average man can own. In the mean time we have an engine with a low efficiency that burns for the most part non renewable fuels.  With this in mind I look at the internal combustion engine as necessary for the next few years and look to see how and where improvements can be made.
The modern combustion engine makes power using four strokes, thus the name four-stroke engine. The first stroke is the intake where a fuel and air mixture is injected into the cylinder from an inlet controlled by a timed cam.
Next, the inlet closes and the mixture undergoes an increase of pressure and temperature as the cylinder compresses the volume.
At the Tmax and Pmax the mixture is ignited with a powerful spark creating and explosion and the power stroke.
The piston captures some of the explosive force and transfers it into the crankshaft.
Finally, the exhaust leaves through another timed cam. As soon as the exhaust port closes the inlet opens and the cycle starts over. 
The modern combustion engine is very similar to the combustion engine of 100 years ago in both material and function. The first patent given for what closely resembles a modern combustion engine was to one Jean Joseph Étienne Lenoir a Belgian engineer.  His design sparked an increase of attention for the internal combustion engine. The catalyst was soon added in the beginning of oil production in the late 19th century.  The reaction was explosive with motor driven carts and eventually automobiles changing the way people transported themselves.
As we increase our oil production and use the world will run out of readily available liquid fuels.  These are the easiest to transport, for example a pipeline, and because of the lack of oxygen and other heavy molecules most energy per kilogram. There are many fuel alternatives but regardless of what they are, more fuel-efficient engines will be vital in making an efficient use of our resources. Most basic improvement have been made over the century have resulted in more reliable, stable and powerful engines. Research into materials and more precise machines have been some of the areas of focus in the past but now we are able to do much more impressive research. With the new E85 fuel they have been able to better optimize engines. With more energy released from its higher heat of vaporization it is able to run in an engine at relatively lean mixtures and avoid knock.  Other benefits are higher compression ratios that can lead to smaller and lighter engines.  Other ways to increase the compression ratios are turbo charging and super charging. Both of these methods work by gaining power from either the exhaust gases or drive shaft and use them in increase the amount of pressure in your cylinders. Turbo chagrining has been around for a while as a way to boost power any in conjunction with smaller lighter engines the short term of engine development seems to be focused on these developments.
© Blake Crowe. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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