压力自适应型机械密封的数值模拟研究

Numerical simulation research on pressure self-adaptive mechanical seal

针对压力自适应型机械密封在高压工况下密封端面变形与密封性能不佳的问题,采用ANSYS中的计算流体力学软件FLUENT和有限元分析软件Mechanical APDL,在15.9 MPa高压工况下分别对密封端面间隙中的液膜流场和密封环进行了数值模拟分析研究,并将计算出的液膜流场状态和密封环变形结果进行了流固耦合求解,进而对液膜厚度对密封性能的影响规律进行了分析,同时对在实际工作状态下,工作压力逐渐上升,密封各性能参数的变化规律也进行了分析。研究结果表明,该密封在高压下的端面变形符合设计需要,密封环端面间的开启工作压力在3 MPa左右,在15.9 MPa高压工况下密封端面间流场的开启力为67.6 kN、泄漏量为0.04 m3/h,平衡膜厚为2.8μm。与其他类型的密封相比,结果显示该种密封能够在高压下提供足够的开启力和在低压下较小的泄漏量。

Aiming at seal face deformation and sealing performance of pressure self-adaptive mechanical seal in the high pressure operating mode, the liquid film of sealing gap and seal ring were simulated and analyzed separately in the operating mode of 15.9 MPa, by using computational fluid dynamics software FLUENT and the finite element analysis software Mechanical APDL, and then the calculated flow state of liquid film and the deformation results of sealing ring were computed in the way of fluid-solid coupling. The influence of liquid film was analyzed on the sealing performance and the variation of sealing performance parameters in the actual working condition of pressure is gradually increased. The results indicate that the seal face deformation meet the design needs in high pressure, and the opening pressure is about 3 MPa. The opening force is 67.6 kN, the leakage is 0.04 m3/h, and the balance liquid film is 2.8μm. Compared with other types of mechanical seals, numerical simulation results indicated that the new type of seal can be able to provide sufficient opening force under high pressure and have a small leakage under low pressure,