Numerical Simulation Study on the Influence of Spray Cooling Process Parameters on the Temperature Field of Dual-Frequency Electric Normalizing for Rails
Due to the presence of coarse grains and other issues in the joint after flash butt welding of rails,it does not meet the performance requirements and therefore must undergo post-weld heat treatment.Common post-weld heat treatment is generally divided into two parts:induction heating and spray cooling.Spray cooling affects the joint structure through the cooling rate and plays a significant role in post-weld heat treatment.In order to explore this process,this paper conducts a numerical simulation of the spray cooling process in the post-weld heat treatment of U75V rail steel based on the fluid simulation software FLUENT.The simulation results indicate that during the normalizing spray cooling,the lowest flow velocity and slowest cooling rate occur at the upper part of the junction between the rail web and the rail head,while the highest flow velocity and fastest cooling rate are found on both sides at the rail bottom.The temperature field during the normalizing spray cooling has the following distribution characteristics:the center of the rail head and rail bottom have higher temperatures,while the rail web has a lower temperature.The heat dissipation capacity of the three,from high to low,is in the order of rail bottom,rail web,and rail head;using different spray cooling pressures at different positions of the cooling box,and employing a method that reduces the spray pressure at the rail web and rail bottom while increasing the spray pressure at the rail head can achieve better cooling effects.
万方数据
维普
