Study On Properties Of New-type Hydrostatic-dynamic Hybrid Lubrication Mechanical Seal

Non-contacting mechanical seal with it's own characters was widely applied inpetrochemical industry field. The interface non-contacting of dry gas seal and upstreampumping seal are depended on fluid's dynamic pressure effect. What is the seal structure ofthis paper studied on is hydrostatic dynamic hybrid lubrication seal whose theoretical basiscomes from hydrostatic dynamic hybrid lubrication bearing and dynamical pressure slot andstatic pressure slot were made on it's rotating ring. Take fluid film as the research object in thispaper, a three-dimensional model was established by Gambit software and meshes weregenerated. Pressure and velocity distribution of interface fluid film was got after numericalcalculation by Fluent software with suitable boundary condition. Compared with static anddynamical pressure seal, the influence law of operating parameters(such as the sealing liquidpressure,rotational speed)to sealing performance were investigated. The results show thatthis kind of seal has the characteristics of dynamical pressure and static pressure seal: smallleakage, great liquid film stiffness, and suitable low-speed non-contact seal. The influence lawof the main structural parameters (dynamic pressure groove depth, static pressure groovedepth, dynamic pressure groove width ratio, static pressure groove width ratio) to sealingperformance was analyzed. After analyzing the relationship curve of structural parameterswith opening force and both sides leakage, the approximate range of each parameter were got,and then the structure of hydrostatic dynamic hybrid lubrication seal has been optimized.Take rotating ring, static ring and fluid film as object a three-dimensional model wasestablished, and temperature fields of rotating ring, static ring and fluid film were studied.What is more the influence law of operating parameters to temperature field was analyzed.This kind of mechanical seal interface temperature rise is no more than 2K with good heatdissipation effect, which is conducive to long-term running. In order to verify the accuracy of numerical simulation, the experimental scheme was made to get the experimental data of bothsides of the leakage under the condition of stationary pressure variable speed and fixed speedvariable pressure. Through analyzing data and comparing with numerical simulation results,the reason why there is difference between experimental data and numerical data was foundand the credibility of the numerical simulation was verified.