基于动网格的上游泵送机械密封性能参数分析

为了准确获得上游泵送机械密封的液膜厚度,采用Pro/E软件建立螺旋槽上游泵送机械密封的三维参数化模型,应用Fluent软件的动网格技术,同时考虑空化的影响,对机械密封微间隙内流场进行了数值模拟.将得到的液膜厚度与有关文献的测试结果进行对比分析.在同时考虑空化模型和动网格技术的基础上,计算分析了工况参数对液膜刚度和泄漏量的影响.结果表明,应用动网格计算的液膜厚度与测试结果所获得的结果基本一致,最大相对误差为19.6%,最小相对误差为0,平均相对误差为8%,从而验证了动网格技术在机械密封内流场模拟中的可行性;机械密封内流场计算应当考虑空化问题,才能得到比较真实的内流场特性;液膜厚度、泄漏量和液膜刚度随着转速、介质压力的增大而增大,端面螺旋槽在产生泵送效应的同时也产生动压效应.

Analyzing performance parameters of upstream pumping mechanical seals based on dynamic mesh technique

In order to get an accurate liquid film thickness of an upstream pumping mechanical seal,a model of 3D flow domain of the seals with spiral grooves was generated by using Pro/E wildfire.The flow field in the micro-gap of the seals with spiral grooved faces was simulated with CFD code Fluent using the dynamic mesh and cavitation model.Liquid film thicknesses under different working conditions were obtained and compared with the experiments to verify the simulated results.And effects of wor-king condition parameters on the stiffness and leakage of liquid film were calculated and analyzed.The results showed that the simulated liquid film thicknesses is basically consistent with the experiments（the maximum,average and minimum errors are 19.6%,8% and 0）,verifying the dynamic mesh technique is feasible for simulating flow field in the gap of a mechanical seal.Also the cavitation problem should be considered in such simulations to obtain real characteristics of the flow field.The thickness,leakage and rigidity of liquid film increase with increasing rotational speed,medium pressure.Further the spiral grooves not only produce a pumping effect,but also generate a dynamic pressure effect.