轴流式止回阀缓冲结构参数对止回性能的影响

Influence of Buffer Structure Parameters on Check Performance of Axial Flow Check Valve

针对轴流式止回阀的止回性能,通过动网格数值试验的方法,采用正交试验设计和极差分析,研究缓冲结构的活塞直径、活塞行程、阻尼孔直径3个结构参数对阀瓣止回性能的影响。分析3个结构参数对止回性能的权重影响;以阀瓣的完全闭合时间及止回过程中的最大液动力为目标进行多目标优化设计,在保证瞬态液动力尽可能小的情况下减少阀瓣的闭合时间,实现“快关缓闭”,提升阀门的稳定性。结果表明:笛形缓冲结构在0.0352 s时,由于通孔面积变化导致缓冲阻尼发生突变,使得阀瓣闭合过程中发生震颤,而改进后的缓冲结构具有恒定的阻尼,提升了阀瓣运动的稳定性;通过对3个结构参数的正交试验结果进行极差分析可知,3个结构参数对于阀瓣闭合时间的影响程度排序为:活塞直径(0.0218)>缓冲行程(0.0178)>阻尼孔直径(0.0135),对于最大液动力的影响程度排序为:缓冲行程(204107)>活塞直径(140362)>阻尼孔直径(140086);缩短阀门的止回时间与减小阀芯振动是两个相悖的目标,不存在唯一的最优结构参数,应根据实际工况选取适当的优化结果。

Aiming at the check performance of axial flow check valve,the effects of piston diameter,piston stroke and damping hole diameter of buffer structure on disc check performance were studied by using dynamic grid numerical test method,orthogonal test design and range analysis.The weight influence of the three structure parameters on check performance was analyzed,and then with disc closing time and the maximum liquid power in the check process as a target for multi-objective optimization design,the disc closing time was reduced under the condition of transient fluid power as small as possible to realize the“fast closing slowly-closing”and improve the stability of the valve.The results show that:at 0.0352 s,the buffering damping of the flute buffer structure changes due to the change of through hole area,which causes the vibration of valve disc during the closing process.The improved buffering structure has constant damping,which improves the stability of the valve disc motion.Through range analysis of the three structural parameters orthogonal test results,it can be seen that the order of influence degree of the three structural parameters on disc closing time is:piston diameter(0.0218)>buffer stroke(0.0178)>damping hole diameter(0.0135);the order of the influence degree on the maximum liquid force is:buffer stroke(204107)>piston diameter(140362)>damping hole diameter(140086).Shortening the check time of the valve and reducing the vibration of the spool are two contradictory goals,there is no unique optimal structural parameter,and appropriate optimization results should be selected according to the actual working conditions.