الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
A continuously variable transmission (CVT) provides an infinite number of gear ratios between two finite limits. This allows the engine to run at its most efficient RPM independent of the car speed, making CVT the most efficient transmission system. The CVT is also fuel efficient, because it reduces the engine speed at high vehicle speed and allows the engine to run at its optimal point. Aiming at determing the behavior of the CVT transmission, a complete mathematical model have been constructed for the whole vehicle equipped with CVT, simulating the whole vehicledynamics. The model takes into Consideration each compnents of the vehicle, including: theengine dry friction disc clutch, belt type CVT, car differential, wheels and body, The slip betweenthe belt and the pulleys and the CVT Traction curvy were also considered.The kinematical, geometrical and momentum equations governing the performance of the whole system were formulated and solved. The governing differential equations were numerically solved In order to predict the behavior of the different mechanical parts of the system. The results of the simulation shows that the system becomes steady after a relatively short period of time. The analysis of the system’s dynamical response demonstrates that the simulation model established represents the system efficiently.In order to compare the behavior of the CVT model with that of a manual transmission, a complete mathematical model is constructed for a vehicle equipped with a conventional manual transmission gearbox. The governing equations of the new model are formulated. These equations are then solved numerically in order to simulate the behavior of the manual transmission gearbox. The graphical representation of the manual transmission system response shows that the system becomes steady after a relatively longer time than the CVT model. The results also show that there are some fluctuations in the angular speeds at the beginning of the motion. The angular speeds of the manual transmission system model become steady at a lower value than that of the CVT model. As a conclusion, the dynamic behavior of the CVT is faster and much more stable than that of an ordinary manual transmission system.