Daniel Barcus Engine Research PaperDocument Transcript
Barcus1Daniel BarcusMs. BennettBritish Literature3 October 2011 The History and Explanation of Engines How much does a person really know about engines and how vehicles function?For manyyears engines have been used to propel many types of vehicles. There are several types ofengines, and those engine types have several sects. The engines summarized in this paper aregasoline, diesel, and Stirling engines. Gasoline engines will be focused on the most, though,because gasoline engines are used in most automobiles today. Each engine serves a purposewhether it is for fuel efficiency, safety, or cost. Stirling engines are basic engines. They are sometimes called “external combustionengines.” When the Industrial Revolution came around, there was a large problem with steamengines. Steam engines would explode, because during the Industrial Revolution people did notunderstand how metal fatigued. Reverend Robert Stirling invented a hot air engine, which is nowcalled a “Stirling engine.” These engines could not explode, and used much less fuel. Theproblem with the Stirling engine is that it would heat up and eventually burn a hole in itself.Despite this problem, Stirling engines were still used until 1915 (Van Arsdell1091-1093).Themain reason Stirling engines are not used today to power vehicles is because Stirling engines runat a constant speed and are not easily able to change speeds on the fly like diesel or gasolineengines (Van Arsdell1093-1094). Stirling engines are powered by heated air. When the air is heated it expands the piston,and when the air is cooled it contracts the engine. One side of the engine is kept heated, and the
Barcus2other side is kept cool. Because one side has constant heat, and the other is constantly cooled, theair cycles throughout the engine. Stirling engines are so versatile that they can be heated by thesun or even by a hot cup of coffee (Van Arsdell1090)! Diesel engines are used today to power many vehicles. They are used in vehicles such aspickup trucks, buses, marine crafts, and road-building equipment. The diesel engine is a result ofmany years of study on internal combustion engines. Sadi Carnot first started working on thisengine, and it was taken on later by ÉtienneLenori. In 1860,Lenori released the first commercialinternal combustion engine. After a few years, Rudolph Diesel finally perfected the internalcombustion engine and added his own type of fuel (Brady 327). He originally wanted to use coaldust as fuel, but modern diesel engines use low-cost oil (“Diesel Engine” 646). Diesel enginesare now called the diesel cycle engines. Today the diesel cycle engine is a reliable engine thatserves many purposes(Brady 327). The diesel engine is a lot stronger than a gasoline engine, mainly because the pistons indiesel engines compress a lot more than gasoline engines do. An average four-stroke gasolineengine has thecompression ratio of between 9:1 and 10.5:1, while an average four-stroke direct-injected diesel engine’s compression ratio is between 15:1 and 17:1. Since the diesel enginecompresses much more than a gasoline engine, the air becomes extremely hot in the dieselengine and ignites the fuel. Diesel engines inject air into the cylinder, and then the air iscompressed. The air heats up to around 1,200-1,700 degrees Fahrenheit. Fuel is then injected intothe cylinder and ignites, pushing the piston backwards (Brady 327-328).Diesel cycle engines aremore powerful than gasoline engines and use cheaper fuel, but they weigh more, are more costlyto produce, and pollute more.
Barcus3 Gasoline engines are the most commonly used engines. In 1698, Thomas Savery inventedthe “Miner’s Friend” which used steam power to pump water. Thomas Newcomen expanded onthe idea in later years and used a piston inside of the engine which produced constant power. In1859, Jean-Joseph Etienne Lenoir invented a durable engine that was reliable. Later, in 1862,Lenoir invented the first automobile. Nikolaus Otto, a grocery salesman, developed the world’sfirst four-stroke engine in 1876. Most modern engines are very similar to the Otto engine (Jensen542-543). There are many parts to a gasoline engine. First there are the engine bearings. Thebearings hold the crankshaft for the pistons in place. The crankshaft runs through the center ofthe engine, holds all of the pistons, and turns when a piston is pushed out or in. The pistons andpiston rings are the heart of the engine. The piston rings keep the pistons air-tight so that whenthe fuel is ignited, none of the energy escapes. The pistons take the full force of the ignition,turning the crankshaft, which in turn turns the timing chains, belts and cam drives. The timingchains, belts, and cam drives turn the camshafts, and sometimes drive pumps for cooling and oil.The camshaft has little egg shapes on it which turn and release the lifters, which open and closethe valves in the piston cylinders. There are two valves per cylinder, one for pouring fuel in andone for letting exhaust out. Finally, there are the spark plugs, which ignite the fuel in thecylinders(“Replacing Engine Parts”). Gasoline engines consist of many parts, and all of the partsneed to work together flawlessly to get the most out of an engine. The gasoline engine converts energy into mechanical work. The gasoline engine is called aninternal combustion engine because the energy inside of the engine comes from the combustionof fuel. The gasoline engine may also be called a spark-ignition engine, because the combustionin the engine is initiated by a spark from a spark plug. Most legal gasoline engines are four-
Barcus4stroke. Four-stroke means that there are four different strokes, or cycles, that the engine goesthrough. The first stroke is the intake stroke. The fuel valve opens and fuel pours into thecylinder. The second stroke is when the fuel valve closes and the piston starts to compress thefuel. The spark plug ignites the fuel and forces the piston out, which completes the third stroke.As the piston starts to go back in, the exhaust valve opens and the exhaust is expelled (Amann557-559). The ignition of the fuel is controlled by an on-board computer, rather than themechanical actions of the engine. (Amann 565) Every time the engine completes its four strokes,the crankshaft turns. Belts are attached to the crankshaft, which turn the camshaft(s). Camwheels attached to the camshaft open and close the intake and exhaust valves. There are differentdesigns for camshafts and valves. For example, sometimes the cam wheels directly push in thevalves, and sometimes cam wheels push an arm which opens and closes the valves. Thecrankshaft also may operate the lubrication and cooling systems. Because of the extreme heatcauses by the ignition of the fuel, a lubrication and cooling system are a must; otherwise theengine could possibly melt. Some engines use water cooling systems, which are mixed withantifreeze. The water, which gathers heat, is pumped around the engine and is brought to aradiator. The radiator increases the water’s surface area, and has a fan attached to it which isturned by the crankshaft. The fan cools the water off quickly in the radiator, so that the water cancycle through the engine again. The crankcase, which the crankshaft sits in, is filled with oil. Apump carries the oil to different parts of the engine (Cohen 2167).Much more plays into enginesthan just pouring in fuel and turning a key. An engine is its own ecosystem, which has differentparts that work together to help each other. So far this paper has talked about the single cylinder in an engine. Unfortunately, mostengines have much more than one cylinder. Engines have many different shapes, as well as
Barcus5different amounts of cylinders. There are four basic cylinder arrangements: V, inline, horizontal,and radial. Radial arrangements were used in older aircraft engines, so they are not as commonas the other three. V engines areself-explanatory because they have the shape of a V. Inlineengines, or vertical engines, usually have all of their cylinders facing vertically, or into the air.Horizontal engines, or flat engines, have two opposite cylinders that are horizontally aligned.Along with the V, horizontal, and inline cylinder arrangements, engines have different amountsof cylinders. The arrangement of the cylinders in an engine can be referred to by the initial of thearrangement and the number of cylinders. For example, a V6 engine would have a V shape andhave six cylinders. An I4 engine would have an inline arrangement and eight cylinders. An H6engine would have a have a horizontally opposed arrangement, and would have six cylinders.Finally, an R5 engine would have a radial arrangement and five cylinders. There is really nolimit to how many cylinders one engine can have, but V6, V8, V10, V12, I3, I5, I6, H6, R5, R7,and R9 are the most common arrangements (Amann 561-562). For vehicles, the arrangement ofthe cylinders really matters on what type of vehicle that the engine is put in to. The arrangementof cylinders does not affect performance by much, though. For example, an H6 engine could putout almost the same power as a V6 engine. An inline engine is hard to cool, so an inline enginewould be good for a small car, but not a larger vehicle. Inline engines also needs only half asmany camshafts as the other type of engines, so inline engines are slightly lighter and morereliable. Horizontal engines have low centers of gravity because they are flat and wide. Vengines are more box-shaped, and have some characteristics of horizontal and inline engines.Some arrangements also might need more metal so they can be mounted correctly. A lot offactors play into arrangement choice, but when it comes down to performance, all arrangementsperform the same (“Is there a difference between inline and V engine configurations?”).
Barcus6 There are many types of engines, but the gasoline engine is the most commonly used.Gasoline engines are used because they are lightweight and very flexible when it comes toconfigurations. Stirling engines are very basic engines which use air and heat to createmechanical energy. Diesel engines are almost a combination of Stirling engines and gasolineengines because they use heated air to ignite fuel, rather than a spark. Every engine is basedaround pistons, which turn a crankshaft that can perform enumerable mechanical tasks. Someengines sacrifice safety for fuel efficiency, give up fuel efficiency for safety, or change cost forboth.
Barcus7 Works CitedAmann, Charles A. “Gasoline Engines.” Macmillan Encyclopedia of Energy.Ed. John Zumerchik.Vol. 2. New York: Gale, 2001. 556-566. 3 vols. Gale Virtual Reference Library.Web. 31 Aug. 2011. <http://go.galegroup.com/ps/ i.do?id=GALE%7CCX3407300128&v=2.1&u=cant48040&it=r&p=GVRL&sw=w>.Brady, Robert N. “Diesel Cycle Engines.” Macmillan Encyclopedia of Energy.Ed. John Zumerchik.Vol. 1. New York: Gale, 2001. 326-366. 3 vols. Gale Virtual Reference Library.Web. 31 Aug. 2011. <http://go.galegroup.com/ps/ i.do?id=GALE%7CCX3407300075&v=2.1&u=cant48040&it=r&p=GVRL&sw=w>.Cohen, M. L. “Internal Combustion Engine.” The Gale Encyclopedia of Science.Ed. K. Lee Lerner and Brenda Wilmoth Lerner.3rd ed. Vol. 3. Detroit: Gale, 2004. 2164-2167. 6 vols. Gale Virtual Reference Library.Web. 2 Sept. 2011. <http://go.galegroup.com/ps/ i.do?id=GALE%7CCX3418501239&v=2.1&u=cant48040&it=r&p=GVRL&sw=w>.“Diesel Engine.”UXL Encyclopedia of Science.Ed. Rob Nagel.2nd ed. Vol. 4. Detroit: U*X*L, 2002. 646-647. 10 vols. Gale Virtual Reference Library.Web. 2 Sept. 2011. <http://go.galegroup.com/ps/ i.do?id=GALE%7CCX3438100223&v=2.1&u=cant48040&it=r&p=GVRL&sw=w>.“Is there a difference between inline and V engine configurations?” HowStuffWorks.Discovery, n.d. Web. 6 Sept. 2011. <http://www.howstuffworks.com/question366.htm>.Jensen, Todd, and P. Andrew Karam.“The Internal Combustion Engine.”Science and Its Times.Ed. Neal Schlager and Josh Lauer.Vol. 5. Detroit: Gale, 2001. 542-544. 8 vols. Gale Virtual Reference Library.Web. 2 Sept. 2011. <http://go.galegroup.com/ps/ i.do?id=GALE%7CCX3408502944&v=2.1&u=cant48040&it=r&p=GVRL&sw=w>.
Barcus8“Replacing Engine Parts.”AA1CAR. N.p., n.d. Web. 7 Sept. 2011. <http://www.aa1car.com/ library/engine2.htm>.Van Arsdell, Brent H. “Stirling Engines.” Macmillan Encyclopedia of Energy.Ed. John Zumerchik.Vol. 3. New York: Gale, 2001. 1090-1095. 3 vols. Gale Virtual Reference Library.Web. 2 Sept. 2011. <http://go.galegroup.com/ps/ i.do?id=GALE%7CCX3407300256&v=2.1&u=cant48040&it=r&p=GVRL&sw=w>.