从突变截面流道内流体满足的方程组出发,给出交变流动中突变截面阻力系数的定义以及考察方法,采用量纲分析法获得影响局部阻力特性的四个无量纲影响参数:动态雷诺数与幅值雷诺数之比、幅值雷诺数、变截面面积比、声场压力、速度相位差。通过PW(粒子成像测速仪)测量,分析了流场结构特征,并与CFD计算结果对比,验证了CFD计算结果的可靠性,进而利用CFD模拟考察了四个无量纲参数对阻力特性的影响规律。
Minor losses for oscillating flow in a duct with sudden area change have been investigated through non-linear theoretical analysis, PIV measurement and CFD simulation. The flow filed was analyzed and results from the PIV measurement and CFD simulation were compared. It shows that the CFD simulation is useful for the flow characteristics analysis in oscillating flow. The influence of the four nondimensional parameters namely the dynamic Reynolds number, Reynolds number, the ratio of the area and the phase difference between pressure and velocity on the minor losses has been analyzed by CFD simulation.