大气道压差对气体滚流强度的影响

Effect of High Port Pressure Drop on Tumble Intensity

在自行研制的气道稳流试验台上研究了发动机气道内大气道压差对气体滚流强度的影响。试验表明,气门升程和气道压差小时,难以形成充分发展的湍流,无量纲滚流强度呈上升趋势,并且波动较大;充分发展时,可压缩气体的滚流强度恒定不变,不可压缩气体的滚流强度比真实值偏大,误差大小只与压力比有关,并随着压力比的增大而增大。

Research has been made on the effect of high pressure drop on tumble intensity in self-made steady flow test rig for port. Based on the experimental results analysis has been made with combination of related theories, which provides references for industrial application. The result shows that it is difficult to make fully developed turbulent at lower valve lift and low port pressure drop, at the same time the non-dimension tumble becomes bigger and bigger along with waving. Under fully developed turbulent flow, the tumble intensity of compressible gas is constant, but the tumble intensity of incompressible gas is bigger than the true value, the error is related only to pressure ratio.