الفهرس 
1. Chapter (1) IntroductionOnly 14 pages are availabe for public view
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Abstract
Supercharging leads to increase the charge density of the working medium inside the engines cylinders which in turn leads to increase the specific power. Numerous techniques were employed to achieve such goal. One of the promising techniques is the pressure wave supercharger. The present work investigates the application of pressure-wave superchargers (PWS) with compression-ignition engines (CIE). This device utilizes the pressure waves issued from the exhaust manifold. These waves transmitted from the exhaust gas side to the air side causing compression effect required for charging process The pressure wave supercharger consists of rotating cylindrical wheel with fixed blades on its periphery in which a constant cross section area passages is obtained The rotor runs inside fixed casing, has different ports for exhaust and charging Additional exhaust gas valve is used to control the charging process called gas pocket valve Modern pressure-wave supercharging devices offer to arbitrarily set gas pocket valve position, cell-wheel speed, and the angle offset between air and gas ports. Since fresh air and exhaust gases are not separated within the cell wheel of the PWS, unforced exhaust gas recirculation (EGR) is possible >The performance of any engine, whether naturally aspirated or supercharged, depends on the processes which take place inside the engine cylinder. Combustion, which is the most important process, is controlled by the amount of air inside the combustion chamber. So, understanding the charging process via PWS plays an important role for governing engine performance and emissions. To achieve this goal, sophisticated model is proposed to simulate the physical process occurs inside PWS This model employs the basic conservation equations of continuity, momentum and energy as well as the species transportation. The gas flow is treated as 1-D, time dependent, and non-reactive compressible fluid flow. These equations can be summarized as the conservation form of the Euler equations. Parameters such as leakage, heat transfer and friction are additionally taken into account. These equations are solved together numerically by using two steps Lax-Wendroff scheme and artificial viscosity. This technique enables to simulate the pressure waves more accurately and precisely. A computer code has been built to simulate the effect of many parameters on PWS performance. These parameters are cells size, rotational speed of PWS, engine speed and the exhaust gas pressure. Synchronization between the engine speed and PWS speed requires mathematical coupling between the engine cycle and PWS. Therefore, cycle simulation is performed taking into consideration the combustion processes, inlet and exhaust valve timing, and the amount of residual gases The concurrence of compression, and expansion waves in the flow field, that is mathematically described by the Euler equations, requires a method that can resolve the pressure-wave motion as well as the gas-air contact surface motion. The flow conditions at the boundaries are treated as closed wall boundaries and also as discharging/ charging condition. In both cases, the effective cross section area at inlet or outlet port is considered The results of the present model are compared with another data [11] to validate the model. The comparison shows fair agreement. The results show that, the opening and closing ports time of PWS is essential to controlling and formatting the pressure waves. The PWS speed has an effect on a volumetric efficiency and the power ratio of the engine. Using 20 % of exhaust gas recirculation (EGR) leads to decreasing the NO emission by 7 %. Synchronization between engine speed and PWS speed is very important.