液力变矩器涡轮高精度建模及流场分析

发布时间：2018-06-24 03:29

本文选题：液力变矩器 + 建模精度　；参考：《华北水利水电大学》2017年硕士论文

【摘要】：模型精度的高低是直接决定液力变矩器仿真结果的关键,通过对影响构建液力变矩器模型精度的各种类型因素进行了分析,提出了一种提高构建液力变矩器涡轮模型精度的新的方法。液力变矩器的三维流线采用三维圆弧和三维直线段设计,三维流线可以看作为由球面和平面的交线,由三维流线方程推导出液力变矩器轴面流线方程,然后再以轴面流线方程为基础,推导了轴面流线的曲率半径和曲率中心坐标的计算公式,采用数值方法可以得到其曲率半径和曲率中心坐标随着极角变化的规律。依据这种变化规律,采用非初等函数分段圆弧一致逼近轴面流线的方法确定逼近圆弧的参数。通过编制参数化程序,对所有方程进行验证。利用程序不仅可以直接得到各段圆弧的圆心坐标、圆弧半径和圆弧起止点的极角,而且还可以直接得到分段圆弧逼近的最大绝对误差和最大相对误差,这便于对结果是否满足精度的要求做出判断。程序设计以及AutoCAD软件与UG软件联合使用,实现了液力变矩器的涡轮的半自动建模。液力变矩器涡轮流道模型构建好之后,将其导入Gambit软件中去划分网格,然后在Fluent软件中进行数值计算,得出其流道内的压力和速度的分布的离散数据;然后对涡行流场规律进行了分析,并和现有文献进行了比对,研究结果表明三维流线采用三维圆弧和三维直线段设计可以改善流场参数分布,进而提高液力变矩器的性能;另一方面也表明这种建模方法能够显著地提高构建模型的精度,具有工程使用价值。
[Abstract]:The accuracy of the model is the key to the simulation results of hydraulic torque converter. A new method to improve the accuracy of building turbine model of hydraulic torque converter is presented. The three dimensional streamline of hydraulic torque converter is designed by three dimensional arc and three dimensional straight line. The three dimensional streamline can be regarded as the intersection line of sphere and plane. The axial flow line equation of hydraulic torque converter is derived from the three dimensional streamline equation. Then, based on the axial streamline equation, the formulas of curvature radius and curvature center coordinate of axial streamline are derived, and the variation of curvature radius and curvature center coordinate with polar angle can be obtained by numerical method. According to this law, the parameters of the approximate arc are determined by the method of uniform approximation of the axial streamline by non-elementary function piecewise circular arc. By programming parameterized program, all equations are verified. By using the program, not only the center coordinates, the radius of the arc and the polar angles of the starting and ending points of the arcs can be obtained directly, but also the maximum absolute error and the maximum relative error of the piecewise arc approximation can be obtained directly. It is convenient to judge whether the result meets the requirement of accuracy. The semi-automatic modeling of hydraulic torque converter turbine is realized by programming and using AutoCAD software and UG software. After the hydrodynamic torque converter turbine runner model is constructed, it is introduced into Gambit software to divide the grid, and then the numerical calculation is carried out in fluent software, and the discrete data of pressure and velocity distribution in the flow channel are obtained. Then, the law of vortex flow field is analyzed and compared with the existing literature. The results show that the three-dimensional streamline design with three-dimensional arc and three-dimensional straight line can improve the flow field parameter distribution and improve the performance of hydraulic torque converter. On the other hand, it also shows that this modeling method can significantly improve the accuracy of modeling, and has engineering value.
【学位授予单位】：华北水利水电大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TH137.332

【参考文献】