Analysis of Heat Transfer Performance According to Installation Conditions of Various Protrusions with Non-uniform Cross-section in Air Space of Air-Type PV/T System

Abstract

Air-type photovoltaic/thermal (PV/T) collectors attached to ducts beneath the solar panels are devices that can recover heat while the panel cools. By contrast, water-type PV/T is easily used because the air of an air-type PV/T has a lower heat capacity than water. A number of studies have been conducted on the installation of ribs as a way to increase the heat recovery capacity of air through ducts. In this study, a protrusion with a non-uniform cross-section was selected to increase the contact area of the air side as well as to promote turbulence. A computational fluid dynamics (CFD) analysis was conducted to confirm the heat transfer performance and the characteristics of the pressure drop according to different shape conditions. As a result, the heat transfer performance was improved by 1.3-to 1.9-fold depending on the conditions of the protrusion installation. However, the pressure drops also increased from 2.534-to 4.685-fold. It is therefore necessary to identify those factors of the thermal hydraulic performance that consider both the heat transfer and pressure drop. As a result, the maximum heat-recoverable shape condition achieved the largest performance coefficient value of 1.24 when e/H = 0.16, P/e = 20, and W p /e = 5.