Effective efficiency of return flow solar air heater

Abstract

In this paper, the effective efficiency of a return flow solar collector with artificial roughness in the form of V shaped ribs is presented as a function of parameters pertaining to roughness like angle of attack (α), and relative roughness height (e/D) and other relevant operating parameters. Analytical methods were used & governing energy balance equations are used to evaluate results. Plots on these aspects have been presented and discussed .It has been found that efficiency is strong functions of roughness parameters. The optimal configuration of the roughness parameters has been determined that yields the best thermo-hydraulic performance for given values of operating parameters. It has been found out that at relative roughness height e/D=0.036, angle of attack α=60⁰ substantial enhancement in the thermal efficiency in the range of 1.2 to 1.7 has been achieved.

Key words: Artificial roughness, Fluid flow, Reynolds number, Solar air heaters

Cite this Article

Vikram Singh, Abhishek Kumar Goel. Effective Efficiency of Return Flow Solar Air Heater. Journal of Refrigeration, Air Conditioning, Heating and Ventilation. 2017; 4(3): 27–32p.