Tuesday, November 08, 2005

Research stuffs take two

Eric Renner
Eng 151 T/TH 12:05
Research Exercise #1 - Exploratory Research/ Take Two
Revised Topic Choices: Alternative Energies and Capitalism
Title of First Encyclopedia Entry “Rudolf Diesel”
Rudolf Diesel
Born: 1857Birthplace: Paris, France
Internal combustion engine—Diesel is best known for his invention of the pressure-ignited heat engine that bears his name. The Diesel engine was able to supplant the large, expensive, and fuel-wasting steam engine. (1976)
Died: 1913 (info please encyclopedia)
Summary with Paraphrase
Title of Second Encyclopedia Entry “Diesel Engine”
diesel engine
diesel engine, type of internal-combustion engine invented by the German engineer Rudolf Diesel and patented by him in 1892. Although his engine was designed to use coal dust as fuel, the diesel engine now burns low-cost fuel oil.
The diesel engine does not require a large water supply or a long warming-up period and is highly efficient in converting heat energy into work. Diesels are widely used in both stationary and mobile installations where the power required is between that furnished by the gasoline engine and that of the steam turbine and where the relatively high initial cost can be written off over a long period. For example, diesels having capacities of 100 to 5,000 hp are employed on industrial and municipal electric generators and on continuously operating pumps (e.g., on oil pipelines). Moreover, they occupy relatively little space compared with steam units, since no boiler is needed—a factor of importance aboard ships. (info please encyclopedia)
Title of Third Source “The Pursuit of Energy Independence” NPR’s Talk of the Nation-Monday, August 1, 2005
Neal Conan with guest
David Friedman, research director of the Clean Vehicles Program at the Union of Concerned Scientists
David Friedman says
“your choice is 16,17, 18 miles per gallon, that’s not a real choice… but the potential is out there, even without hybrid technology, with simple conventional technology, to have an SUV that get 30, 35 miles to a gallon, that would be real choice in the market place and that way it wouldn’t be about giving up something, it would be about getting the same size the same performance you get today, but with dramatically higher fuel economies so you can save thousands of dollars on gasoline, and, reduce our imports.”
“If it’s that easy, why isn’t it there?” asks Neal Conan
“That’s the classic question” replies David Friedman “and the reason in many ways is because it’s a question of industry being relatively short sighted. The, especially the auto industry, they’re concerned about their profits two days, two weeks, maybe even two months from now. They’re not investing in technologies, they’re not investing in these opportunities that are going to ensure they’re profitable ten years from now. That’s one of the ways that some of the foreign auto makers are actually standing out. They are investing in these technologies, they are planning for the future.”
Title of Fourth Source “Automobile Service” by Tim Gilles (Textbook for Arizona Automotive Institute)
Then and Now:
The Automobile Industry (ch. 1)
On January 29, 1886, Karl Benz of Mannheim, Germany, patented the worlds first automobile, the three wheeled Benz Motorwagen. Later that same year, Gotlieb Daimler of Cannstadt, Germany, built a four wheeled car. Its 1.5 hp engine had 50% more power than the Benz; the horsepower race had begun. In 1900, Benz’s company became the biggest company in the world, building 603 cars.
Long before Benz’s patent, there were ingenious automotive inventors and tinkerers in the United States. But the 1896 Duryea of Massachusetts was the first car to be produced in the United States, followed shortly by the Haynes and Winton. in 1900, Ransom E. Olds of Detroit become the first to mass-produce automobiles in America, the curved-dash “merry Oldsmobile” of the song “Come Away with Me, Lucille.”
Henry Ford was the first to produce the automobile in mass quantities. His grand idea was to build a car that everyone could afford. In 1903, the current Ford Motor Company was founded. The first Model T was sold in 1908. In its 19-year run, 15 million copies of that rugged, simple automobile were produced. This record was not surpassed until the Volkswagen Beetle did so in the early 1970’s.
Another early automotive giant was General Motors, which in 1908 bought Buick, Oldsmobile, Cadillac, and Oakland (which would become Pontiac). Within 2 years, thirty firms had been brought under the GM umbrella, including eleven auto makers.
Walter P. Chrysler merged Willys and Maxwell-Chalmers in 1920. The first car to bear the Chrysler name went on sale in 1924 and was a huge success.
A current trend among foreign car makers is to build assembly plants in the United States. This idea is far from new. In 1888, Steinway and Sons, the New York piano maker, obtained the rights to sell all Daimler patents in the United States. It produced engines and cars in this country between 1905 and 1907.
Today, between one in nine working Americans build, sell, or fix and maintain motor vehicles. Automobile dealerships account for 29% of the retail business conducted in the United States. Automotive-related business represents about a third of a trillion dollars worth of our nation’s economy in an average year. It is estimated that $150 billion of that total is spent on parts, repairs, and maintenance.
Title of Fifth Source “Diesel Engine and Fuel System Repair” by John F. Dagel and Robert N. Brady
Gasoline versus Diesel Engines (p.44)
The thermal efficiency, or heat efficiency, of a diesel engine is superior to that of the spark-ignited gasoline (Otto cycle) engine. As we know from information discussed earlier in this chapter, the diesel engine employs compression ratios much higher than those of a gasoline engine. This is necessary to create a high enough cylinder air temperature for the injected to vaporize and start to burn. The much higher combustion pressures and temperatures allow a greater expansion rate and more energy to be extracted from the fuel. Tremendous improvements have occurred in gasoline spark-ignited engines, particularly in the 1990s when fuel consumption improvements due to changes in engine component design, combustion improvements, and electronic control of distributaries ignition and fuel injection systems have resulted in thermal efficiencies in the area of 32 to 35%, and as high as 39%. Gasoline engines tend to return better fuel economy when held at a steady speed, such as during highway driving, but the suffer in city-driving cycles because of the intake manifold air-throttling and pumping losses that occur at lower speeds.
Diesel engines, on the other hand, do not suffer from a throttled air supply and operate with a stratified air charge in the cylinder under all operating conditions. The net result of the unthrottled air in the diesel engine is that at idle operation and light loads, the air fuel ratio in the cylinder is very lean (90:1 to 120:1). This excess air supply lowers the average specific heat of the cylinder gases, which in turn increases the indicated work obtained from a given amount of fuel.
To comply with EPA exhaust emissions standards, automotive gasoline engines have to operate close to stoichiometric air/fuel ratio, which is approximately 14:1. In other words, about 14kg of air is required to completely combust 1kg of fuel. Another way to look at this is that approximately 10,000 L of air is required to burn 1 L of gasoline. Even under full-load operating conditions the diesel engine operates with an excess air factor of at least 10 to 20%, which usually results in air/fuel ratios in the region 20:1 to 25:1. To meet exhaust emissions standards the gasoline engine relies on the exhaust-gas oxygen sensor to constantly monitor the “richness” or “leaness” of the exhaust gasses after combustion. This oxygen sensor sends update information continuously to the on-board ECM (electronic control module) to allow operation in what is commonly known as closed-loop operating mode. Failure of the oxygen sensor results in the engine falling into an open-loop mode (no signal to the ECM), and the ECM automatically resorts to a “limp-home” condition that allows the engine to run but at a reduced performance. Because of their excess air factor of operation, most diesel engines at this time do not need an exhaust-gas oxygen sensor, or a catalytic converter, although some light- and midrange mechanically controlled truck engines are equipped with converters.
Another advantage that the diesel engine enjoys over its gasoline counterpart is that diesel fuel contains about 11% more Btu per unit volume than that in gasoline. Therefore, the diesel engine would have a better return per dollar spent on fuel.
Title of Third Encyclopedia Entry “Steam Engine”
steam engine
steam engine, machine for converting heat energy into mechanical energy using steam as a medium, or working fluid. When water is converted into steam it expands, its volume increasing about 1,600 times. The force produced by the conversion is the basis of all steam engines. Steam engines operate by having superheated steam force a piston to reciprocate, or move back and forth, in a cylinder. The piston is attached by a connecting rod to a crankshaft that converts the back-and-forth motion of the piston to rotary motion for driving machinery. A flywheel attached to the crankshaft makes the rotary motion smooth and steady. The typical steam engine has an inlet valve at each end of the cylinder. Steam is admitted through one inlet valve, forcing the piston to move to the other end of the cylinder. This steam then exits through an exhaust valve. Steam from the other inlet valve then pushes the piston back to its original position, and the cycle starts again. In a single-cylinder steam engine the exhaust steam is usually expelled directly into the atmosphere. A compounded steam engine has several cylinders, which the steam passes through successively until, leaving the last cylinder, it is condensed into water and returned to the boiler. From the Greek inventor Heron of Alexandria to the Englishmen Thomas Newcomen and John Cawley, many persons contributed to the work of harnessing steam. However, James Watt's steam engine, patented in 1769, provided the first practical solution. Earlier engines depended on atmospheric pressure to push the piston into the cylinder, where a vacuum was created by sudden cooling of its steam content. Watt's use of a separate condenser resulted in a 75% saving in fuel. It also made possible the use of steam pressure to move the piston in both directions. Watt's continuing efforts produced a governor, a mercury steam gauge, and a crank-flywheel mechanism, all of which prepared the steam engine for a major role in the Industrial Revolution. Sailing vessels gave way to steamboats, and stagecoaches yielded to railroad trains as the steam engine was perfected. Transmitted by belts, ropes, shafts, pulleys, and gears, the energy from steam engines drove machines in factories and mills. Now, however, steam engines have been replaced in most applications by more economical and efficient devices, e.g., the steam turbine, the electric motor, and the internal-combustion engine, including the diesel engine. They are still sufficiently economical to be used in industries where steam is necessary for some purpose in addition to that of driving an engine.
See C. W. Pursell


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