风电塔筒法兰锻件自然对流传热试验与模拟

Experiment and simulation of natural convection heat transfer of tower cylinder flange forgings for wind power

通过热电偶测温和模拟研究了高径比为1.05的S355NL圆柱形铸坯空冷过程的温度场,分析了测量温度和模拟温度差异的原因。计算了对流传热与辐射传热的占比,对流传热约占40%。研究了工件倾斜角对换热的影响,工件温度分布沿重力反方向逐渐升高,对于倾斜圆柱锭坯,沿轴线方向向上,温度逐渐升高,主要是由于热边界层增厚,导致传热效率降低。局部努塞尔数的分布规律与温度分布规律呈相反趋势,随倾斜角度增大,工件表面的平均温度逐渐升高。

The temperature field of S355NL cylindrical casting billet(the height-to-diameter ratio was 1.05)in air-cooling process was studied by thermocouple temperature measurement experiments and simulation analyses.The proportion of convective heat transfer and radiation heat transfer was calculated,respectively.It was found that the convective heat transfer accounted for about 40%.The effect of workpiece inclination angle on heat transfer was investigated.The temperature distribution of the workpiece gradually increased along the opposite direction of gravity.For the inclined cylindrical forging billet,the temperature gradually increased along the axis direction.It was due to the thickening of the thermal boundary layer,which resulted in a reduction in heat transfer efficiency.The distribution law of local Nusselt number was opposite to that of temperature distribution.The average temperature of the workpiece surface gradually increased with the increase of inclination angle.