ISSN Online: 2379-1748
ISBN Flash Drive: 978-1-56700-472-4
ISBN Online: 978-1-56700-471-7
3rd Thermal and Fluids Engineering Conference (TFEC)
HEAT TRANSFER ENHANCEMENT IN A HEAT EXCHANGER HAVING TWO ROWS OF ROUND TUBES AND SLIT FINS USING VORTEX GENERATORS
Compact heat exchangers with just a few rows of tubes are frequently used in the air conditioning and refrigeration industry. The trend at this moment aims to build surfaces with a higher thermo-hydraulic performance, looking to reduce the heat exchange areas and lowering costs during the production process. This paper is about the enhancement of heat transfer in a slit fin having two rows of tubes in a staggered array. A passive enhancement technique using vortex generators was used. The vortex generators location is investigated and the best one among the studied is found. The best location of vortex generators produces a thermal performance higher than the slit fin in smooth condition ranging from 4.9% to 12.35%. On the other hand, the pressure drop was increased up to 22.4%. Surfaces in smooth conditions and using vortex generators are compared using the "volume goodness factor" resulting in a positive effect of vortex generators on the slit fin surface. Vortex generators of Delta Winglet type with a unitary aspect ratio are used. The flow and temperature fields are investigated to explain local results. The study was made inside the laminar regime using Computational Fluid Dynamics. The numerical method is validated against published experimental results and almost a perfect match was found. All results presented in this paper were obtained from independent mesh solutions.