低气压条件下电加热器自然对流换热性能测试

从理论上分析了表面传热系数与气压的关系,实验测试了电加热器在低压与常压下的换热性能,得出以下结论:低压与常压下表面传热系数的比值与气压比值的0.2次幂成正比;电加热器在低压与常压下散热功率基本相等;表面温度随气压的降低而升高。

Testing of natural convection heat transfer performance of electric heaters under lower air pressure

Theoretically analyses the relations between the surface coefficient of heat transfer and air pressure.Experimentally tests the heat transfer performance under lower air pressure and normal air pressure.Concludes that the ratio of surface heat transfer coefficients under lower air pressure to that under normal air pressure is in direct proportion to 0.2 power of the ratio of lower air pressure value to normal air pressure value,that the heat emission power under lower air pressure is almost equal to that under normal air pressure,and that the surface temperature rises when air pressure falls.