铜钢复合冷却壁传热及热应力分析

Heat transfer and thermal stress analysis of copper steel composite stave

通过建立铜钢复合冷却壁传热及热应力分布数学模型,研究了铜钢复合冷却壁与铜冷却壁、铸钢冷却壁的传热性能差异及其铜钢界面热应力分布。结果表明:煤气温度为1200℃时,高炉内无渣皮覆盖铜钢复合冷却壁肋热面最高温度为180℃,较相同煤气温度下铜冷却壁的最高温度高约30℃,较铸钢冷却壁的最高温度低约520℃。铜钢复合冷却壁具备铜冷却壁的传热性能。铜钢界面边缘正应力σz大于0,表现为受拉状态;冷面增加加强筋后,铜钢界面边缘正应力σz小于0,表现为受压状态,且最大等效应力降低至114.45 MPa,低于铜钢复合板的高温强度。高炉内铜钢复合冷却壁不会发生铜钢界面分离破损。热态试验中铜钢复合冷却壁温度计算值与测量值吻合较好,验证了数学模型的准确性。

The heat transfer difference of copper steel composite stave with copper stave and cast steel stave and thermal stress distribution of copper steel interface were investigated through establishing a mathematical model of heat transfer and thermal stress distribution of copper steel composite stave. The results show that the maximum temperature at the rib of copper steel composite stave without the accretion is 180 ℃ when the furnace temperature is 1200 ℃, which is about 30℃ higher than that of copper stave and 520 ℃ lower than that of cast steel stave. Copper steel composite stave has the same heat transfer performance as copper stave. The normal stress σ2 at the free edge of copper steel interface is larger than 0 and it is submitted to tension. When welding the copper steel composite stave onto the reinforced rib, the normal stress σ2 at the free edge of copper steel interface is lower than 0 and it is submitted to compression, and the maximum equivalent stress of copper steel interface decreases to 114.45 MPa and it is less than the elevated temperature strength of copper steel composite plate, Copper steel composite stave will not be damaged by separation of copper and steel layer in blast furnace. The calculated and measured temperature of copper steel composite stave in the thermal test agree well, which verifies the validity of the mathematical model.