干气密封端面平衡间隙的研究

Research on the Balance Clearance of Dry Gas Seal

为了确定干气密封端面平衡间隙的数值,基于N-S方程、层流模型、SIMPLEC算法,对干气密封端面流场进行数值模拟,获得端面气膜开启力的数值。将开启力和闭合力变化曲线同时绘出,两曲线交点所对应的端面间隙即为该干气密封的端面平衡间隙值。以某泵用干气密封为例,介绍了闭合力和开启力的计算,确定出该干气密封的端面平衡间隙。结果表明,干气密封端面平衡间隙值应取在开启力随间隙变化幅度较大的小间隙区域,且端面平衡间隙应在泄漏量不超标的前提下,尽量取得大一些,使密封端面接触和摩擦可能性和程度降到最低,从而提升干气密封运行稳定性。

For the balance clearance of dry gas seal, the numerical simulation of face flow field was carried out based on the. Navier-Stokes equation,laminar model,and SIMPLEC methods, and the opening force of face film was gained. Drawing the curve of opening force and closing force at the same coordinate, fingering out the intersection point, so the corresponding face clearance of this point is tbe balauce face clearance. Through an example, the method to calculate the opening force and closing force was introduced, the balance clearance was gained. The numerical results shows that best balance clearance is at small clearance zone with opening force changing acutely, for the lower feasibility of contact and friction, greater clearance value should be selected on the condition of no excessive leakage, thereby, higher stability will be gained.