Keywords

Solar Still, Numerical Simulation, Performance

Abstract

To improve modeling of solar still behavior, the convection correlations currently used need to be improved upon. Variations in operating parameters and cover geometries make it difficult to use a single correlation to describe the operation of all solar stills. In this work, three right triangles (representing covers at 15, 30, and 45 deg) were modeled, meshed, and solved to predict the convection heat transfer inside for a variety of operating conditions. For a correlation of the form Nu = C · Raⁿ, it was found that C = 1.1, 0.60, and 0.71, and n = 0.19, 0.24, and 0.24 for 15, 30, and 45 deg, respectively. A grid dependency study implied error of up to 37% for the computational fluid dynamics data (and therefore the correlation). The correlation is useful for Rayleigh numbers ranging from 2.9 × 10³ to 7.1 × 10⁸, with error up to 37%. The correlation showed some reasonable agreement with Shruti’s correlation, and extends the range of Rayleigh numbers over which an estimate for the Nusselt number can be made. The results here also verify the need for a correlation that accounts for specific cover geometry.

Original Publication Citation

LeFevre J., Jerry Bowman W. and Jones M. R., “Numerical Simulation of Convection in Triangular Cavities to Predict Solar Still Performance,” Journal of Thermophysics and Heat Transfer, Vol. 27, No. 3, 2013, pp. 482–488. doi:https://doi.org/10.2514/1.T4025 JTHTEO 0887-8722