DOI: 10.1615/ICHMT.2014.IntSympConvHeatMassTransf
ISBN Print: 978-1-56700-356-7
ISSN Online: 2642-3499
ISSN Flash Drive: 2642-3502
EXPERIMENTAL AND THEORETICAL ANALYSIS OF A MICROCHANNEL HEAT EXCHANGER FOR HIGH CONCENTRATION PHOTOVOLTAIC CELLS
RESUMO
HCPV (High Concentration Photovoltaic) systems operate more efficiently once the solar cell is kept cooled by suitable heat sinks. Most of the commercial HCPV systems are based on passive air-cooling systems, especially due to their simplicity and robustness, while here an alternative approach is considered to remove heat more efficiently from the photovoltaic cell, replacing the passive air-cooled system with an active water-cooled one, and also allowing the re-use of the removed heat in a secondary circuit for other purposes, such as water desalination. In this context, this work presents the manufacturing process, the experimental procedure and theoretical analysis of an optimized micro heat exchanger for active cooling of a commercial HCPV module that concentrates 1200 suns, using water as the working fluid. The optimized micro-heat exchanger, with 18 micro-channels of 400μm in width and 945μm in depth each, was manufactured in copper using a CNC micro-milling machine and then characterized in a 3D digital microscope. An experimental apparatus was assembled to analyze the proposed micro-heat exchanger in both controlled and realistic situations, comprised in four distinct experimental runs. A non-intrusive infrared camera thermography system has been employed to measure the temperature at the external surface of the micro-heat exchanger substrate, while in the theoretical study the commercial simulation platform COMSOL Multiphysics 4.2a was adopted, allowing for critical comparisons of experimental and theoretical findings.