时间步长对淬火过程温度场和组织场模拟精度的影响

淬火过程是一个温度、相变、应力应变相互影响的高度非线性过程,在用有限元方法计算温度场和组织场时,极易造成数据振荡现象.本文针对淬火过程温度场的特点,为了尽量提高温度场和组织的计算精度,使用集中热容矩阵、网格细化和自适应时间步长的方法,编写了淬火过程有限元模拟程序,并提出了一种控制模拟时间步长的方法--基于最大和最小温差的自适应步长,该方法是用前一步模拟得到的温度场与当前步模拟所得的温度场的差值控制模拟时间步长.用编写的程序对轴对称零件进行有限元模拟,从模拟结果的对比中可以看出,基于最大和最小温差的自适应步长方法不但可以避免数据振荡和提高模拟精度,而且可缩短计算模拟的时间.

Effect of Time-Step on Simulating Precision of Temperature and Phase-Transformation Field During Quenching Process

Quenching process is a high non-linear process with the interaction of temperature, phase-transformation and stress/strain. When the temperature field of quenching is evaluated using finite element method, the numerical oscillation is easily caused. In order to improve the precision of the temperature and phase-transformation field in quenching process, the methods of lumped and consistent mass matrices, mesh refinement and self-adaptive time step are used and a finite-element simulating program for evaluating the temperature and phase-transformation is developed in this paper. A new method of self-control and adaptive time-step is presented according to the maximum and minimum difference values of temperature field between the previous symmetric problem is evaluated using the simulating step and the current simulating programmed self-adaptive time step method presented in this paper cision is improved,and the computation time is much step. The quenching process of axisoftware. The comparison of the simulation results shows that the can effectively avoid the numerical oscillation. The evaluating preless than those of other methods.