Internal-combustion automobile engine

The Otto cycle is essentially the cycle describing the internal-combustion automobile engine. This is a four-stroke cycle, in contrast to the simpler two-stroke Carnot cycle and the various others, such as the Stirling and Brayton cycles, that operate on a single oscillation of the piston. The Otto cycle consists of an intake expansion, a compression, an expansion resulting from ignition... 

The internal combustion automobile engine has been developed to a remarkably high degree in terms of its emissions. The ultimate development of such an engine is one claimed to be so clean that when it is operated in a smoggy atmosphere, its exhaust is cleaner than the air that it is taking in ... 

A four-stroke internal combustion engine was built by a German engineer, Nicholas Otto, in 1876. The cycle patterned after his design is called the Otto cycle. It is the most widely used internal combustion heat engine in automobiles. 

Variable valve timing is being developed to improve the performance and reduce the pollution emissions from internal combustion heat engines for automobiles and trucks. A unique benefit for these engines is that changing the timing of the intake valves can be used to control the... 

Sirtori, S., P. Garibaldi and F.A. Vicenzetto (1974), Prediction of the combustion properties of gasolines from the analysis of their composition . SAE paper No. 74-1058, International Automobile Engineering and Manufacturing Meeting, Toronto, Ontario. 

Catalyst—-An Exhaust Cleaning Technology for Automobiles with Internal Combustion Engines), VDI-Berichte 630, VDI-Vedag, Dusseldorf, Germany, 1984. 

Fuel cells, which rely on electrochemical generation of electric power, could be used for nonpolluting sources of power for motor vehicles. Since fuel cells are not heat engines, they offer the potential for extremely low emissions with a higher thermal effidency than internal combustion engines. Their lack of adoption by mobile systems has been due to their cost, large size, weight, lack of operational flexibility, and poor transient response. It has been stated that these problems could keep fuel cells from the mass-produced automobile market until after the year 2010 (5). 

At the beginning of the twentieth centuity, the automobile was still a novelty. In the United States more cars were then powered by steam engines and bat-teity-electric systems than by internal-combustion engines. By the end of the twentieth century, the automobile had become an integral part of the American lifestyle, with approximately one privately... 

When the automobile became preeminent in the early twentieth century, it did so with good reason. Wliether the energy to power a bicycle is anaerobic or aerobic in nature, it is still minuscule in comparison to what an automobile s internal combustion engine can deliver. In the United States, almost all subcompact cars are equipped with engines that can generate 100 or more horsepower (74,600 watts), and can sustain this output all day long. 

Transportation accounts for about one-fourth of the primary energy consumption in the United States. And unlike other sectors of the economy that can easily switch to cleaner natural gas or electricity, automobiles, trucks, nonroad vehicles, and buses are powered by internal-combustion engines burning petroleum products that produce carbon dioxide, carbon monoxide, nitrogen oxides, and hydrocarbons. Efforts are under way to accelerate the introduction of electric, fuel-cell, and hybrid (electric and fuel) vehicles to replace sonic of these vehicles in both the retail marketplace and in commercial, government, public transit, and private fleets. These vehicles dramatically reduce harmful pollutants and reduce carbon dioxide emissions by as much as 50 percent or more compared to gasoline-powered vehicles. 

At the end of the nineteenth century, virtually all of the gasoline produced (around 6 million barrels) was used as a solvent by industry, including chemical and metallurgical plants and dry cleaning establishments, and as kerosene for domestic stoves and space heaters. But by 1919, when the United States produced S7.5 million barrels of gasoline, S5 percent was consumed by the internal combustion engine (in automobiles, trucks, tractors, and motorboats). 

Large-scale crude oil exploitation began in the late nineteenth century. Internal combustion engines, which make use of the heat and kinetic energy of controlled explosions in a combustion chamber, were developed at approximately the same time. The pioneers in this field were Nikolaus Otto and Gottleib Daimler. These devices were rapidly adapted to military purposes. Small internal-combustion motors were used to drive dynamos to provide electric power to fortifications in Europe and the United States before the outbreak of World War I. Several armies experimented vith automobile transportation before 1914. The growing demand for fossil fuels in the early decades of the twentieth centuiy was exacerbated by the modernizing armies that slowly introduced mechanization into their orders of battle. The traditional companions of the soldier, the horse and mule, were slowly replaced by the armored car and the truck in the early twentieth century. 

Rain unaffected by human activity contains mostly weak acids and has a pH of 5.7. The primary acid present is carbonic acid, H2C03, a weak acid that results when atmospheric carbon dioxide dissolves in water. The major pollutants in acid rain are strong acids that arise from human activities. Atmospheric nitrogen and oxygen can react to form NO, but the endothermic reaction is spontaneous only at the high temperatures of automobile internal combustion engines and electrical power stations ... 

During the 1800s, benzene was of limited commercial value, finding use mainly as a solvent. But after the invention of the internal combustion engine and the automobile, it was found that motors ran better when the fuel contained benzene. This added a new economic incentive to recover all of the benzene possible from the steel industry s coke ovens. However, just prior to World War II, the importance of benzene as a chemical intermediate started to be recognized. These dual incentives (gasoline and chemical intermediate) led to new and improved benzene processes based on petrochemistry rather than coal. 

Schafer, A., J.B. Heywood, A. Malcolm, Weiss, Future fuel cell and internal combustion engine automobile technologies A 25-year life cycle and fleet impact assessment. Energy, 31, 2064-2087,2006. 

---