迷宫流道内固体颗粒运动的CFD模拟及PIV验证

CFD Numerical Simulation and PIV Verification about the Movement of Solid Particles in Labyrinth Channel

针对迷宫流道灌水器结构细微复杂的特点,分别采用计算流体动力学CFD模拟方法和粒子图像测速仪PIV观测方法,对固体颗粒在迷宫流道内的运动规律进行了模拟研究与试验观测,并对2种方法的研究结果进行了分析,结果表明:CFD模拟不同直径、不同密度的固体颗粒运动时,其模拟轨迹线与实际运动线非常接近;当颗粒直径较小(65μm)或密度较小(镁粒,1 740 kg/m3)时,CFD模拟的颗粒通过的路程与实际运动路程的偏差很小,而直径或密度较大的颗粒偏差比较大,其原因是直径或密度较大的颗粒实际运动时更加靠近主流区;采用CFD模拟颗粒运动速度是可行的,但颗粒实际运动时,保持高速的时间长于CFD模拟。

Considering the structural intricacy of the drip irrigation emitter with labyrinth channel, this paper utilized the numerical simulation method by CFD and observation method by PIV to simulate and observe the movement regulation of the solid particles in labyrinth channel, and analyzed the results of the two methods. The results show that the movement trajectories of the solid particles with different diameter and density calculated by CFD software accord with the actual movement trajectories observed by PIV machine well. When the diameter is 65 μm or the density is 1 740 kg/m^3, the difference of the path length between the numerical simulation by CFD and observation by PIV is very little, but it is big when the diameter or density is big as the actual movement of solid particles are more closing to the mainstream. It is feasible to simulate the velocity of solid particles by CFD software, but the time of the high speed of particles can keep longer than the simulation one.