Analysis of Heat Transfer and Solar Radiation Absorption in an Irradiated Thin, Falling Molten Salt Film

Abstract

A study was conducted to investigate the heat transfer characteristics of an irradiated, gravity-driven semitransparent fluid flowing over an opaque substrate. The physical model simulated is prototypical of cavity-type solar central receivers. Both absorption and emission in the fluid were considered, while scattering was neglected. The effects of model parameters such as substrate emissivity, fluid layer opacity, spectral nature of incident radiative flux, flow model, and fluid layer physical thickness were investigated. Results are presented for fluid mixed mean temperature and collector efficiency along the layer length in order to evaluate the performance of such systems.