摘要
设计了针对泵腔和平衡腔的液体压力测试装置,采用同一块压力传感器测量不同测点压力的方法,对不同直径平衡孔前、后泵腔和平衡腔的液体压力进行了测试及分析。试验发现,对这种前后密封环直径相同的叶轮,在密封环正常时密封环以上的前、后泵腔液体压力分布是不同的,且后泵腔液体压力普遍较前泵腔液体压力高。基于有、无液体泄漏泵腔液体压力曲线的分析,引入了泵腔液体压力损失系数,提出了设计工况有液体泄漏泵腔液体压力计算公式及其压力损失系数的具体确定方法。并用2台离心泵泵腔液体压力测试结果,验证了设计工况有液体泄漏泵腔液体压力计算公式具有较高的可信度。比较分析了设计工况平衡腔液体压力的理论计算结果和试验结果,验证了设计工况平衡腔液体压力数学模型能准确地预测出平衡腔液体压力,并从控制平衡腔液体泄漏量减少其液体压力及轴向力的角度,提出试验泵的平衡孔直径在6~8 mm较为合适。
A special testing apparatus was designed for measuring and calculating fluid pressure in pump chamber and balance cavity,fluid pressure in front-back pump chambers was measured and analyzed by changing balance hole diameter and using a pressure sensor. It was found that liquid pressure in back cavity was generally bigger than that in front cavity under normal conditions of seal ring,and the curves of fluid pressure in front-back pump chamber above the diameter of seal ring were different. Based on systematical analysis of pressure curve of pump chamber with or without fluid leakage,the computational formula of fluid pressure in pump chamber with fluid leakage was presented by introducing pressure loss coefficient under the design condition. The fitting formulas of pressure loss coefficient were given by calculation of experimental data under the design condition. Moreover,the theoretical calculation results and the experiment results of fluid pressure in pump chamber with fluid leakage had also been contrasted and analyzed for two centrifugal pumps. The results showed that the computational formula of fluid pressure in pump chamber with fluid leakage had high credibility. Fluid pressure in balance cavity was calculated using mathematics model under the design condition. The experiment results proved that this mathematics model could accurately forecast fluid pressure in pump chamber. In order to control the fluid leakage and reduce the axial thrust,it was proposed that the balance holes diameter of 6 ~ 8 mm was appropriate through analyzing the theoretical calculation results and experimental results.
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2016年第8期42-47,324,共7页
Transactions of the Chinese Society for Agricultural Machinery
基金
国家自然科学基金项目(51269010)
甘肃省自然科学基金项目(1508RJYA077)
浙江省自然科学基金项目(LY12E09002)
关键词
离心泵
泵腔
平衡腔
液体压力
试验
数学模型
centrifugal pump
pump chamber
balance cavity
fluid pressure
experiment
mathematical model
