自动调节式发动机进气管试验

通过对４９２ＱＳ汽油机进气管的结构分析，设计带有节门的新型进气管，使其随转速的变化能自动打开或关闭，利用模拟计算的结果，在理论上进行分析对比，优化出最佳进气管。同时对原机的进气管也进行模拟计算。在此基础上对不同长度的进气管进行模拟计算，然后按优化的长度加工进气管，并设计了节门控制电路。最后对原机进气管和新设计的进气管装机进行实测。试验结果表明利用节门的打开和关闭可使发动机能兼顾高低转速时的性能指标

EXPERIMENTAL STUDYS ON AN ENGINE WITH AN AUTOMATIC CONTROLLED INTAKE PIPE SYSTEM

A newly designed intake system of 4920S gasoline engine with automatically controlled valve to make the intake pipes longer or shorter for high or low engine speeds in order to get higher volumetric efficiency and better performance is investigated. Calculations are made for this type of intake system with different pipe lengths and the original intake pipe by using MK14 program. The data are analyzed and the optimum pipe construction lengths are selected. The data are analyzed and the optimum pipe construction lengths are selected. The electronic control unit of the valve has been disigned and tested. Experiments are made on a 492Q model gasoline engine mounted with this type of intake pipes of different pipe length and the original pipe for comparison. The test results show that the engine performance can be improved significantly by mounting the intake system with a controlled valve, the engine maximum power output are raised in a average of 9.67% than the original intake pipe when the valve is closed, and the maximum torque was 12.4% when the valve of the intake pipe was opened.