aduate Studies Performance Characteristics of A turbo Charged Engine with E G R

Abstract

( NO x ) Is a generic term for mono-nitrogen oxides (NO and NO2). These oxides are produced during combustion, especially combustion at high temperatures. At ambient temperatures, the oxygen and nitrogen gases in air will not react with each other. In an internal combustion engine, combustion of a mixture of air and fuel produces combustion temperatures high enough to drive endothermic reactions between atmospheric nitrogen and oxygen in the flame, yielding various oxides of nitrogen. In areas of high motor vehicle traffic, such as in large cities, the amount of nitrogen oxides emitted into the atmosphere can be quite significant. When ( NO x ) and volatile organic compounds (VOCs) react in the presence of sunlight, they form photochemical smog, a significant form of air pollution, especially in the summer. Children, people with lung diseases such as asthma, and people who work or exercise outside are susceptible to adverse effects of smog such as damage to lung tissue and reduction in lung function. Mono-nitrogen oxides eventually form nitric acid when dissolved in atmospheric moisture, forming a component of acid rain. Refer to this problem; many techniques are created to minimize the ( NO x ) emissions from IC engines, one of the most famous techniques used to reduce the ( NO x ) is Exhaust Gas Recirculation (EGR). The idea of the EGR system is to add some amount of cooled flue gas to mixed with fresh air in the intake manifold, this will tend to decrease the combustion temperature and eliminate the availability of air in the cylinder. Here in this research, a study of performances of IC engine with addition of EGR was carried out. Chapter two contains some literature review for turbocharger and the parameters that affecting engine performances as compression ratio, pressure ratio and Exhaust gas recirculation, also chapter three holds, how nitrogen oxides forms and description of the EGR system and it classifications, also this chapter contains other emissions control techniques. The data used are obtained from computing software simulation (Diesel – RK), before the study take place a calculations model was derived so as to help and remind the reader with all thermodynamics and combustion relationships. Then a computing program is build, this program will be very helpful for using a different engine specifications. A mathematical relation between (PR, CR, N, EGR, and NO x ) was been created from the data extracted from software, this step is important because it is necessary to compare and evaluate the error of this data with experimental data. The engine parameters are affected when adding the EGR as a brake power will reduces when EGR ratio increases in a same manner the brake thermal efficiency will decreases, also the specific fuel consumption will effected, one of the most interesting characteristics of the engine is the rate of nitrogen oxides production in which is reduces greatly when EGR ratio increases. II