Wind-induced convective heat loss of cylindrical receiver considering the effect of dish concentrator

摘要

A numerical model by coupling Monte Carlo Ray Tracing (MCRT) and Computational Fluid Dynamics (CFD) was built to explore the convective heat loss of a cylindrical receiver with built-in coiled tube. Noted that the non-uniform heat flux boundary of the receiver was obtained by optical simulation and the effect of existence of the dish concentrator was taken into account. The variation of flow field and convective heat loss with inclination alpha, wind direction phi, wind velocity V were analyzed in detail. The results indicate that the presence of concentrator in a windy environment can significantly interfere with the air flow thus affecting the convective heat loss of receiver, and such effect gradually weakens with the increase of alpha. Except for the case of phi = -90 degrees and 0 degrees <= alpha <= 17 degrees, the convective heat loss with concentrator is always less than that without concentrator. The effect of phi on convective heat loss is complicated and has a great relationship with both V and a. In most cases except for phi = 0 degrees, the convective heat loss takes on a trend of first decreasing and then increasing with varying a. Additionally, a Nusselt number correlation for predicting the convective heat loss of receiver under the effect of dish concentrator was proposed.

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