蒸汽直接冷却槽式太阳集热器的传热流动性能研究

THERMAL PERFORMANCE AND HYDRODYNAMIC ANALYSIS OF DIRECT STEAM GENERATION SOLAR COLLECTORS

首先在对DSG集热器中水的流型分析的基础上,进行了水在不同状态下对流换热系数计算模型的研究;利用传热热阻原理,分析了DSG集热器热损失的计算方法;考虑到流体流动方向上的温度变化,建立了稳态热传导模型。之后,对集热器的两种不同连接方式(一次通过式和再循环式)的压降进行了分析。最后,分析了太阳能辐射变化时,两种连接方式下集热器场一些主要参数的变化情况,为DSG集热器场的设计及运行提供指导。

A direct steam generation collector （DSG） has been proposed as a future development of the parabolic trough solar collector technology. Researches on its thermal performance and hydrodynamic are performed. Firstly, convective heat transfer coefficients of water at different phases are studied based on the flow patterns analyses; Heat loss is formulated based on the thermal resistances theory; Heat transfer model under steady-state is developed considering temperature variation along fluid flowing. Then pressure drop is calculated for two different DSG collector system concepts, oncethrough process and recirculation process. Finally, the variation of some main parameters in a DSG collectors field is evaluated at different radiation levels for these two modes.