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Intake flow for a four-stroke experimental gasoline engine is modeled considering moving valves and realistic port geometries. The numerical model is based on the KIVA-3 code and computed flow velocities are compared with LDV measurements. Computations start prior to intake valve opening and the pressure boundaries are specified at both the intake and exhaust pipe cross sections. Numerical results show that the in-cylinder flow pattern is well simulated in the symmetric plane passing through the cylinder axis. The computed and measured cylinder pressure and flow velocities agree reasonably well during the intake process. At top-dead-center, computations show a rotating flow pattern exists in the squish region corresponding to an area with relatively high turbulent kinetic energy. Results of intake flow modeling also show the evolution of in-cylinder averaged turbulent kinetic energy is different if the intake charging process is not modeled.

This paper describes a simulation package developed for predicting the dynamic performance of passenger cars and motorcycles under standard driving cycle test conditions. The package is a combination of a transient engine performance synthesis, a set of algorithms of driveline dynamics, a chassis dynamometer model, and a fuzzy driver behavior model. These models are described in simple mathematics in this paper. The paper also demonstrates simulation results of the performance of a passenger car tracking the USA FTP 75 test cycle, and a motorcycle under ECE R40 test cycle conditions. (These two cycles are currently adopted by the Taiwanese Government as the standard driving patterns for passenger cars and motorcycles respectively.) The results show that the simulation package is extremely useful for the motor industry to determine the design specifications and control strategies before a prototype vehicle is produced.