Determination of the heat transfer coefficient by convection, according to shape of the baffles (solar air collector)

Abstract

This experimental study and mathematical modelling aim to improve the heat transfer by convection in different cases of transversal baffles inside a duct of a solar air collector. The study enabled us to formulate a mathematical equation of the heat transfer coefficient as a function of pressure drop and the mass flow rates. This mathematical model gave results that are close to the actual results in different inclination angles of the baffles (45°, 90°, 135°, and mixed between 135°and 45°). Through these results, it is found that the best heat transfer coefficient by convection was in the mode where = 90° and in the mixed mode. It was also noticed that the pressure drop in the mixed mode was smaller. With respect to the thermo-hydraulic performance factor (THPF), the case =45° was retained as the best case.

Keywords

• heat transfer coefficient
• convection
• baffles
• pressure drop
• mass flow rate
• solar collector