A Multi-Body And Multi-Physical Coupling Model Of Hydrodynamic Mechanical Seals In Rcps And Seal Performance Analysis

Hydrodynamic mechanical seals etched millimeter deep grooves on the end face have been widely used in crutial machinery—reactor coolant pumps (RCPs) in nuclear power plants. At present, the technology of exploring such kind of products is immature in China, so it is of great influence in theory and enginnering to develop mechanical seals with independent intellectual property rights and to break the monopoly of foreign companies. To investigate the seal mechanism of hydrodynamic mechanical seal and the seal structure design method, and to promote the development of related design theory, in this dissertation, the following work is completed,Firstly, based on the multi-body geometrical characteristics of mechanical seals, taking the the contact and fluid-solid coupling between seal components into consideration, a multi-body and multi-physical coupling mathematic model for seal assembly is developed. A numerical iteration algorithm is introduced to solve the mathematical model, which lies the foundation for the following work. The influence of different operating condition on seal performances is studied. Secondly, the influence of different structure parameters of the seal rings on the deformation of the end face and seal performance. The feasibility is disscued to control the circumferential deformation and radial deformation of the end face by choosing the reasonable structural parameters.Theoretical results show that,(1) the seal mechanism of hydrodynamic mechanical seal is verified through the3D multi-body and mutil-physical coupling mathematic model and numerical algorithm.(2) the structural parameter of seal rings greatly influence the radial taper deformation of seal end face, while the millimeter deep groove structure have important role on the circumferential wave deformation, which shows independence of the two kind of structure parameters.(3) the U shaped deep grooves in OD is the major reason of circumferential wave formation, and the grooves in ID slightly increase the waviness. The model, the numerical method and the conclusion stated by this dissertation can be used to guide seal structure design in hydrodynamic mechanical seal.