小流量工况下背叶片对重型渣浆泵磨损的影响

针对重型渣浆泵在偏离设计工况运转时出现的局部磨损情况进行了研究,应用Particle模型对重型渣浆泵高浓度浆体输送进行数值模拟,并通过试验验证,分析了节流设计的重型渣浆泵在小流量工况运转时,叶轮前后背叶片的设计对泵内部局部磨损的影响.研究结果表明:节流设计的渣浆泵在小流量工况下运行时,内部流场比设计工况下更加不稳定,扬程下降3%~10%;护套内部颗粒体积分数的分布受前后背叶片影响很小,但对颗粒滑移速度会产生明显影响;当设计有前后背叶片的重型渣浆泵在小流量工况下运行时,护套与转子交界靠近隔舌处固体颗粒的滑移速度激增,产生严重的局部磨损,严重影响使用寿命;通过去除前后背叶片,可以有效降低交界处的颗粒滑移速度,减轻磨损程度;但前背叶片的去除也会造成前腔回流量大幅增加,使前腔内部旋涡强度增大,加剧前护板内侧的磨损.

Influence of back blade on wear of heavy slurry pump under low flow condition

Considering the wear caused by the application of heavy slurry pump operating under conditions deviating from design conditions,the Particle model was used to simulate the transport of high-concentration slurry in the heavy slurry pump and the experimental verification was carried out.The influence of the front and back blades of the impeller on the local wear of the heavy slurry pump with throttle design under the low flow condition was analyzed.The results show that the internal flow field of slurry pump with throttle design is more unstable than that of slurry pump under the low flow condition.The head drops by 3%-10%.The front and back blades have little effect on the particle volume fraction distribution inside the jacket,but have significant effects on particle slip velocity.When a heavy slurry pump with the front and back blades operates under low flow conditions,the slip velocity of solid particles at the interface between jacket and rotor near the tongue will increase sharply.It will cause serious local wear and seriously affect its service life.The removal of the front and back blades can effectively reduce the particle slip velocity at the interface to reduce wear.However,the removal of the front blades will also lead to backflow increase in the front cavity,which will increase the vortex intensity in the front cavity.As a result,the wear of the inner side of the front guard plate is aggravated.