Unsteady Gas Flow Through Reed Valve Induction Systems

It is possible to predict the unsteady gas flow behavior and the performance and noise characteristics in a naturally aspirated two-cycle engine. A mathematical model has been formulated to simulate the action of the two-cycle engine fitted with a reed valve due to unsteady gas dynamic behavior in the inlet tract. A complete computer simulation of a two-cycle engine fitted with a reed intake valve is thus possible. The mathematical model of a cantilever beam vibrating in the first three modes, as applied to the two-cycle engine reed valve and employing a completely theoretical forcing function, is particularly advantageous in view of the fact that a subsequent mathematical model formulated to predict reed behavior in the simulator could do so accurately for milder forcing pressures than would be experienced in the firing two-cycle engine. The complete program for a reed valve two-cycle engine will provide a significant design tool and will effect savings in development time and costs. The complete program predicts all noise and performance characteristics and will include reed petal motion. Designed elements will be petal length, width, thickness, inclination, and number for a given petal material.