基于数值计算的制动电阻元件表面传热系数研究

Research on the Surface Heat Transfer Coefficient of Brake Resistor Element Based on Numerical Method

在传统制动电阻设计中,获得电阻元件表面传热系数主要依靠设计经验或者定型产品的温升试验数据,并没有定量的计算方法。为了准确计算制动电阻运行过程中的瞬态温度变化情况,验证制动电阻设计方案的可行性,利用数值计算方法对制动电阻元件表面传热系数进行了研究,以稳态条件下求出的表面传热系数为基础,建立了电阻元件的瞬态温升计算模型,并综合分析了导热和辐射换热对电阻元件温度的影响。通过与制动电阻产品温升试验数据的对比,验证了该瞬态温升计算模型的准确性,为制动电阻工作温度的模拟提供了简便高效的方法。

In the traditional design, the surface heat transfer coefficient of brake resistor mainly came from experience or temperature-rise test data, and was not calculated by formulas. In order to calculate the transient temperature-rise of the brake resistor, and validate the design of the brake resistor, a research on the surface heat transfer coefficient of brake resistor element based on numerical method was carried out, and a model for calculating the transient temperature-rise was built based on surface heat transfer coefficient of steady condition. The influence of heat conduction and radiation heat transfer on brake resistor element temperature-rise was also analyzed. By comparing the results with temperature-rise test, the transient temperature-rise model was verified, which provided a simple and effective method for brake resistor temperature calculation.