Numerical Simulation And Optimization Of The Intake Port For JE4D28A Diesel Engine

Effective and low emission engine has become an inevitable trend for the more serious environment problem. And the design of intake port take an important role in engine designing process. It's a key part for a achieve efficiency and low emission engine, which affects flow characteristic and consequently affects combustion condition in cylinder.Traditional design method often used experience with steady flow test,which takes lots of time and cost.However, the method that integrate numerical simulation with steady flow test to study air situation of intake port can get flow characteristic easily and clearly. It can cut down development time, and reduce development cost, and provide support and base to intake port analysis, evaluation and optimization.The intake port of a specific diesel engine are studied in this paper.Three cylinder heads with same types in one batch were used to do steady flow test.According to flow coefficient and swirl rate of three cylinder heads in test, Ricardo average evaluation parameters were calculated and the deviation of flow coefficient and swirl rate is relatively small, which indicates consistency of these three cylinder heads are pretty well.A three dimensional model of JE4D28 A diesel engine intake port was built by CATIA software. Using the data from steady flow test to set the boundary condition,Flow Simulation of intake port was done by AVL-FIRE software. Flow coefficient,swirl rate, velocity distribution map were calculated. And it shows that the error between simulation and test is under 5%, and numerical simulation on intake port designing is reliable.Three optimized design schemes for the intake port were proposed according to related articles and experience. After simulation calculation, compared the simulated flow coefficient and swirl rate of three schemes and initial engine when the lift is 4 mm, it shows that increasing angle of tangential intake port can optimize flow characteristics, which reduce swirl rate and increase flow coefficient appropriately. Then the flow distribution of optimized scheme are calculated, andthe velocity tangential maps are compared with that of initial designing, which proves the feasibility of this scheme.