牙轮钻头单金属密封数值模拟与优化

针对钻井过程中牙轮钻头金属密封磨损严重、对井底振动比较敏感的问题,利用有限元软件对高压工况下的单金属动密封进行数值模拟,在此基础上利用逆解法对动密封面的泄漏率进行求解。结合正交实验设计确定出优化变量,采用Box-Behnken实验方法建立了单金属密封优化响应面模型,最后采用罚函数寻优法建立基于泄漏率最小的优化模型,并优化了密封的结构参数。结果表明,优化后单金属密封的性能得到了有效的改善,密封泄漏量得到降低,端面接触压力分布更加均匀,同时,验证了响应面优化法在单金属密封接触压力及泄漏量优化中具有可行性。

Numerical Simulation and Optimization Research on Single Metal Sealing of Cone Bit

For the problem of the serious wearing of metal sealing of cone bit and its sensitivity to the bottom hole vibration during drilling process, the finite element software was used to simulate the dynamic sealing of single metal under high pressure. The leakage rate of dynamic sealing surface was solved by inverse method. Based on the orthogonal experimental design, the optimization variables were determined and the response surface model of single metal sealing optimization was established by Box-Behnken experimental design method. The penalty function optimization method was used to establish the optimization model based on the minimum leakage rate and the structural parameters of the sealing were optimized. The analysis results show that the performance of the optimized single metal sealing is effectively improved. The distribution of contact pressure is more uniform, and the feasibility of response surface optimization method in the optimization of contact pressure and leakage of single metal sealing are also verified.