【摘要】 根据Hirs湍流润滑理论提出了一种计算部分锥度环状间隙短密封压力场及动力特性系数的方法。密封中的周向流动和轴向流动均假设为湍流状态。对Hirs湍流润滑方程的求解采用摄动法 ,由相应的零阶近似方程可求得稳态周向速度分布 ,压力分布及密封泄漏量 ;对短密封作类似于计算短轴承的处理 ,使一阶近似方程得到适当简化 ,方程的解给出扰动压力的表达式 ,对其进行数值积分便可确定各个动力系数。针对计算中出现的锥度变化处未知量对轴向坐标导数不连续问题提出了相应的解决措施。计算结果与现有实验结果比较一致。通过实例计算分析了全锥度密封在不同磨损程度下动力特性系数的变化情况 ,并将部分锥度密封动力特性系数与平密封以及全锥度密封进行了分析比较更多还原

【Abstract】 A combined analytical and computional method based on Hirs’turbulent lubrication equations was presented to calculate the pressure field and dynamic coefficients for partial tapered short annular seals. The flow is assumed to be completely turbulent in the axial and circumferential directions. Linear zeroth and first order perturbations were developed.The zeroth order equations were solved numerically to yield the axial and circumferential velocity components,the pressure distribution and leakage rate. A short bearing approximation was used to simplify the first order equations and to derive an analytical expression for the first order pressure gradient.This expression is integrated numerically to define dynamic coefficients. For the discontinuity of derivatives at taper variation,a corresponding solution was proposed. Numerical predictions show generally good agreement with available experimental results. The effects of wear and taper length/total length ratio on the seal rotordynamic coefficients were presented.更多还原