Experimental investigation and optimization of potential parameters of discrete V down baffled solar thermal collector using hybrid Taguchi-TOPSIS method

Abstract

• Hybrid Taguchi-TOPSIS optimization of discrete V down baffle in solar air channel. • CFD analysis to evaluate the difference in contribution of potential parameters. • The Nu opt and f opt for the optimum set have founded 165 and 0.061 respectively. • Secondary stream generation and mixing with primary stream stimulates turbulence. The thermo-hydraulic performance of solar thermal collector can be significantly improved by the utilization of roughness geometries in the fluid flow channel. However, the experimental investigation of turbulence promotors is a tedious and costly process. Thereby, the hybrid Taguchi-TOPSIS technique has been utilized in this work for optimization of potential parameters of discrete V down baffle in the fluid flow duct of the collector. The potential parameters of the discrete V down baffle have been selected, the relative angle of attack (α/90), relative discrete width (g w /H b ) and relative discrete position (D d /L v ). The experimental alternatives are decided by Taguchi’s L 16 orthogonal array. The optimization of potential parameters and ranking of alternatives based on the closeness index has been conducted. The optimum values of potential parameters have been found to be α/90 = 0.666, g w /H b = 1 and D d /L v = 0.67. The quantification of contribution percentage for each potential parameter on the performance of solar air heater has been conducted and found to be 33.29%, 37.25% and 29.46% for α/90, g w /H b and D d /L v respectively. The CFD analysis of solar air channel (SAC) with discrete V down baffle has been carried out for understanding the fluid flow and heat transfer mechanism, the performance of the optimum set of potential parameters and the difference in the contribution of potential parameters. This study will be beneficial for researchers and designers for optimization and understanding the effect of potential parameters on the performance of solar thermal collector utilizing air as working fluid.