Thermal performance of packed-bed solar air heaters

Abstract This paper presents an experimental investigation of the enhancement of thermal performance of solar air heater having its duct packed with blackened wire-screen matrices. Tests were conducted to cover wide range of influencing parameters including geometry of wire screens, mass flow rates and input solar energy fluxes under actual outdoor conditions. Effect of these parameters on the thermal performance has been investigated and results have been compared with those of plane (flat-plate) collectors. These tests provide useful data for rating wire-screen matrices packed-bed collectors based on thermal performance. It is observed that the performance of plane collector improves appreciably by packing its duct with blackened wire-screen matrices and this improvement is a strong function of bed and operating parameters.

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