在厚板淬火过程的数值模拟中,换热系数的正确求解是保证其温度场及应力场模拟结果与实际结果一致的前提。在实测冷却曲线的基础上建立了换热系数求解的两种数学模型,计算了换热系数随淬火时间关系曲线。基于ABAQUS模拟软件分析了两种模型在某特定区域温度场的实测与模拟误差。结果表明,换热系数随时间呈非均匀分布,在20~40 s之间出现换热系数峰值;一点法求解的换热系数优于两点法;两种方法计算的表面温度均出现温度回升现象,但一点法求解的表面温度回升较两点法的平缓。
In numerical simulation of thick-plate quenching process,Precise solution of heat transfer coefficient is the precondition of simulation of temperature field and stress field.Two mathematical models of the solution of heat transfer coefficient were established on the base of cooling curves of actual measurement,the relation curves of heat transfer coefficient and quenching-time were calculated.The actual and simulated temperature fields in specific point of two models were analyzed by ABAQUS FEM.The results showed that the distribution of heat transfer coefficient by quenching-time was non-uniform,and appearing peak value of heat transfer coefficient in 20 to 40 s.The solution of heat transfer coefficient by two-point model was superior to one-point model's.Both of the two models appeared temperature rally's phenomenon in calculating surface temperature,but the surface temperature's rally by one-point method solving was more gentle than that of two-point method.