Intake And Exhaust Flow Field Simulation Analysis Of Engine Switching Between Two-Stroke And Four-Stroke

In this paper, basing on Honda SDH125-2-type four-stroke engine, I will build two or four-stroke switching engine mathematical model and use experimental data on the four-stroke mode to modificate the parameter in computational fluid dynamics simulations of the engine intake and exhaust flow field. Use the revised data to simulate the intake and exhaust flow field of two-stroke mode to find suitable Valve Timing for two-stroke model, it can provide a theoretical basis for the design of camshaft for two-stroke models.This paper described the basic principles of computational fluid dynamics, computational fluid dynamics basic control equations in detail; introduced the procsee of building the two or four-stroke switching engine combustion chamber, cylinder layering, intake and exhaust port,intake and exhaust valve layering models basing on Honda SDH125-2-type four-stroke engine,and introduced the simulation pre-treatment method of meshing models, setting boundary conditions in details; At last, use he revised parameters to simulate the intake and exhaust flow field with three kinds of intake and exhaust Valve Timing for two-stroke mode, analyzed and compared the simulation results to determine a suitable intake and exhaust Valve Timing for two-stroke model and provided theory for the two-stroke model camshaft design.In this paper, I took out the method of using the engine intake and exhaust flow field computational fluid dynamics simulations to design the engine intake and exhaust Valve Timing, it can increase the efficiency of the engine research and development, and meet the design requirements effectively.