Assessment of compact heat exchanger consisting entirely of tubes arranged in a turbulence generating mesh

Abstract

The performance of a novel liquid-air heat exchanger is experimentally evaluated and compared with that of several commercial automotive radiators having louvre fins and flat tubes. The coils were assessed using a closed loop test rig which has the capability of simulating ambient conditions of any habitable place on earth. The prototype heat exchanger was designed to generate three dimensional vortical motion using an open mesh structure, to enhance heat transfer without incurring high pressure loss penalties. When compared with respect to the available heat transfer surface area, the heat transfer capacity, and the heat transfer coefficient were increased. Also the pressure drop was well below that of the conventional radiators. However, in a direct comparison the overall the heat transfer capacity fell short of expected commercial radiator requirements.

Keywords:

• Compact tube-fin heat exchanger
• vortex generator

Additional information

Notes on contributors

C Allison

Colin Allison began his academic pursuit with a diploma in Mechanical Engineering from the Natal Technikon in South Africa. He then spent two years working for SASOL 2, which is a petrochemical plant manufacturing petrol from coal. Returning to study, he graduated cum laude from the University of Natal with a degree in Mechanical Engineering. After several years work experience with Building Service Consulting Engineers, he returned to do a masters degree in Energy Studies this time at the University of Cape Town. He then returned to the Consulting environment working for one of the major South African Building Services Consulting Engineering firms. In 2000 he emmigrated to Sydney to take a position with Vos Group Consulting Engineers. After two years he was awarded a scholarship to do a PhD in Mechanical Engineering at Adelaide University. His research topic is on improving the air side heat transfer coefficient of tube-fin heat exchangers. His other areas of interest are natural ventilation and passive air-conditioning in buildings, renewable energy and CFD modeling. He is an accredited practitioner with AIRAH.

B Dally

Dr Bassam Dally graduated from the Technion in Haifa in 1988 with a BSc in Mechanical Engineering. In 1991 he joined the School of Mechanical Engineering at The University of Sydney as a researcher assistant and 1993 he was awarded a Australian Postgraduate Award scholarship to pursue his postgraduate studies. In 1998 he graduated with a PhD in Combustion Science. In 1998 he accepted a lectureship position at the School of Mechanical Engineering at the University of Adelaide. Since then Dr Dally was promoted to a senior lecturer position and he has been the deputy head of school for the last three years. His research interest is in the area of thermo-fluids and includes Heat transfer, Combustion, Laser Diagnostics, Fluid mechanics and CFD. He has published some 55 papers in scientific journals and national and international conferences. He supervises six PhD students and has attracted more than $1.8 million in funding. He is an executive member the Australia and New Zealand Section of the Combustion Institute, Australasian Fluid & Thermal Engineering Society (professional society of IEAust) and the Energy Cluster at Adelaide University. He is also a member of ASHRAE and International Combustion Institute.