椭圆管外强化凝结放热过程研究

Heat Transfer of Enhanced Vapor Condensation Over Elliptical Pipe

本文对椭圆管外蒸汽凝结放热过程进行了理论和实验研究,推导出椭圆管外静止饱和蒸汽凝结放热准则方程式,并分析了一些主要参数对凝结放热系数的影响.在实验研究中,对换热周长相同、长短半轴之比(a/b)不同的椭圆管外蒸汽凝结放热系数在不同工况下进行了测试,得到凝结放热实验曲线.论证了椭圆管相对于圆管来说能强化蒸汽凝结放热.理论分析与实验结果比较,表明两者吻合较好.

The heat transfer of enhanced vapor condensation over the surface of an elliptical pipe has been studied theoretically and experimentally. An equation of dimensionless parameters for the condensation of vapor in a static saturated state was derived, and the effects of some major parameters on the heat transfer coefficient of vapor condensation were analyzed and discussed. The heat transfer coefficients over the surface of elliptical pipes with the same perimeter but with different ratios of major and minor axes were measured experimentally to yield some experimental curves. The theoretical analysis was in good agreement with experimental results. The heat transfer of vapor condensation over an elliptical pipe was greater than that over a circular pipe.