颗粒直径对渣浆泵冲蚀磨损性能的影响

为探究渣浆泵在输送固液两相流介质时颗粒直径对冲蚀磨损的影响,采用k-ε湍流模型(液相)、离散相零方程模型(固相)和Finnie塑性冲蚀磨损模型,通过拉格朗日法计算出不同颗粒直径下颗粒的运动轨迹.对颗粒与过流零件表面撞击的冲击速度、冲击角度等参数进行了数值模拟,进而探讨固液两相流中浆体对渣浆泵的磨损规律.结果表明:小直径颗粒在流道中分布相对均匀,与过流部件发生撞击概率很小,对叶片的冲蚀磨损相对较弱.大直径颗粒的运动轨迹易向叶片工作面靠拢,且易与叶片头部发生碰撞.直径较大时,颗粒冲击叶片和蜗壳圆周壁面的角度和速率更大,且存在多次撞击过程,对叶片和蜗壳壁面的冲蚀磨损程度相对较大,造成严重的冲蚀磨损.

Effects of particle diameter on erosion wear performance of slurry pump

In order to investigate the influence of particle diameter on erosion wear performance of slurry pump delivering solid-liquid two-phase flow medium, the motion trajectory of particles with diffe-rent particle diameter is calculated based on Lagrange method, k-ε turbulence model, discrete phase zero equation model and Finnie ductile materials erosion model. The impact velocity, impact angle and other parameters between solid particle and machine surface were evaluated by numerical simulation, and the wear rule of solid-liquid two-phase flow in slurry pump are discussed. According to the simulation results,the particles with small diameter distributed relatively uniform in the flow path, had a very small probability of in collision with the hydraulic components, and the erosion wear of the blade was relatively weak. By contrary,the solid particle with large diameter was apt to move toward to the pressure surface and impacted the leading edge of the blade.The impact angle and velocity of the particles with large diameter was greater to the blades and the volute circumferential wall than the small ones, and the erosion wear of the blade was relatively strong. And the large particles might in collision with the hydraulic components many times in the flow channel, causing serious erosion.