基于水平集方法的软性磨粒两相流场特性分析

为了解决模具结构化表面精密加工(SAFM)过程中软性磨粒两相流场特性参数难以求解的问题，提出一种基于水平集法 (LSM)的磨粒流场特性分析方法. 基于LSM结构拓扑变换原理，结合流体体积模型(VOF)计算方法，建立面向软性磨粒两相流湍流流型分析的动力学模型. 通过高阶TVD Runge-Kutta、迎风格式以及高阶本质无振荡(ENO)方法分别对水平集时间项和空间项进行离散，且利用N-S方程和压力耦合方程的半隐相容(SIMPLEC)算法，实现软性磨粒两相流场的压力、速度等特性参数的求解. 以工程中常见的90°方形弯管为具体仿真实验对象，研究软性磨粒两相流流经管道过程中的速度场与压力场变化. 实验结果表明，数值计算结论与直管处速度场试验结果是一致的，验证了该方法的有效性，为软性磨粒流精密加工方面的研究提供了可靠的理论依据.

Analysis on characteristics of softness abrasive two-phase flow field based on level set method

In order to solve the characteristic parameters of softness abrasive two-phase flow field in the structural surface mould manufacturing process, a method based on level set method (LSM) for flow field characteristic parameters was proposed. Based on the topological structure transformation of LSM, combining volume of fluid (VOF) method, a two-phase dynamic model of abrasive flow oriented to the soft abrasive flow machining (SAFM) was established for physical parameters analysis. The high order TVD Runge-Kutta, up-wind differencing and high-order accurate essentially non-oscillatory (ENO) schemes were applied for calculating the temporal and spatial discretization of the governing equations. The characteristic parameters of the abrasive two phase flow, such as pressure and velocity, were derived by the Navier-Stokes equation with Semi-Implicit Method for Pressure Linked Equations Consistent (SIMPLEC) algorithm. With 90° square bent tube as specific simulation object, the velocity field and pressure field variations were studied based on this softness abrasive two phase flow model. The simulation results were in accordance with the test results in the straight tube. which verified the validity of the proposed method, and confirmed the feasibility of SAFM.