PROF JOSUA MEYER
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What is your field of specialty, and could you please give a brief explanation of it?
My speciality is heat transfer. Heat transfer conveys energy from a high temperature to a lower temperature. The mechanisms of heat transfer are defined as conduction, radiation and convective. In convective heat transfer the heat transfer might be external forced convection, internal forced convection, or natural convection. Heat transfer has many applications and happens everywhere.
The human body is constantly generating and/or rejecting heat by metabolic processes and exchanged with the environment and among internal organs by conduction, convection, evaporation, and radiation. Heat transfer is also one of the most important factors to consider when designing household appliances such as a heating and air-conditioning system, refrigerator, freezer, water heater, personal computer, mobile phone, TV, etc.
Heat transfer also occurs in many other applications such as in car radiators, solar collectors, orbiting satellites, etc. However, one of the most important applications is in the generation of electricity which can happen in fossil fuel power plants, nuclear power plants or concentrating solar plants. The heat transfer during the generation of electricity happens in heat exchangers which normally has at least one passage through which a fluid flows. The passage geometry can be as simple such as a circular tube or it can have a very complex geometry with fins that not only enhances the heat transfer but induces flow rotation. These enhancements can significantly reduce the size of a heat exchanger.
For all these configurations empirical correlations are required for design and analyses purposes that can be used to estimate heat transfer rates. To develop thousands of empirical equations are not desirable as we first need to have a better understanding of the fundamentals and flow phenomena. Furthermore, different flow regimes (laminar, transitional or turbulent) normally each require its own empirical equations. Thus, to be able to understand complex heat transfer flow phenomena in complex geometries we must first understand what happens in simple geometries, such as in circular tubes.
How would you say your research contributes to the concept of “research for impact”?
The impact of my research is that it is a fundamental speciality that needs to be used to improve the efficient consumption and generation of power, such as electricity. The generation and efficient consumption of energy is one of the worlds (and South Africa’s) most important and demanding challenges. Providing adequate energy that meets the requirement of a growing world population with the aspirations of rising living standards will require major advances and new technologies in energy supply, efficient consumption and generation. Both producing and consuming more energy while mitigating the risk of climate disruption will be an even more challenging endeavour. At the same time it will be important to phase out the consumption of fossil-fuels. The biggest challenges will be in developing countries and countries which are dependant of fossil-fuels. Their choices of technologies and policies will have significant implications on their growth, international competitiveness, and economic security and prosperity.
What does attaining an A-rating mean to you professionally, and personally?
I started at the bottom with a Y-rating and have slowly progressed to an A-rating. The A-rating clearly demonstrates that I am not static in terms of research, and it encourages me to keep on publishing high quality articles in high impact journals.
I have to give credit for obtaining an A-rating to all the talented postgraduate students and colleagues I have had the privilege to supervise and lead. A number of them have since moved on to new roles all over the world, not only at universities but also in industry. This opened up avenues for research collaboration, student and staff exchange as well as external funding.
What do you enjoy most about your job and what are the aspects that you find challenging?
When my students and I make research breakthroughs on aspects we have been researching for many years. For example, just recently on a problem we have been working on for more than 10 years.
What is the biggest piece of advice that you would give early-career researchers and those who are aspiring to become leaders in their respective research fields?
Focus on high quality research outputs in top archival journals rather than on quantity. Make sure your productivity compares well with your peers. An excellent article now is better than to strive for a perfect paper later that never gets published. Also, identify the world leaders in your field, get onto an aeroplane and visit them with the purpose to collaborate. They would know what the major and most important challenges in your field are.
What do you do for fun (apart from research!)?
Reading and watching TV.
Prof Josua Meyer, was in April 2022 appointed as a professor at Stellenbosch University. Before this appointment he was a professor at the University of Pretoria. During his professor term he was the Head of Mechanical and Aeronautical Engineering (1 900 students) for 20 years, and Chair of the School of Engineering (7 000 students) for 17 years.
His research has a broad focus on the thermal sciences, but with a narrower focus on heat exchangers. His heat exchanger work focuses on fundamental work in internal forced convection, the transitional flow regime, nanofluids, boiling, and condensation. On an applications level his work focuses on thermal-solar, wind- and nuclear energy. He has grown this research group to approximately 30 full-time graduate students and 10 staff members. During this time he also established various labs with state-of-the-art instrumentation and designed and constructed (with his group members) more than 12 unique experimental set-ups.
He has received 11 different national teaching awards from three different universities, as well as an international award. His videos on heat transfer on YouTube has been watched more than 1.7 million times. He has won more than 43 research awards including 33 awards for best article of the year or best conference paper. International/national awards were given to 12 of his postgraduate students for the quality of their work under his supervision.
For his research he has won the following national and international awards: Thomas Price Award, Rand Coal Award, South African Institute of Mechanical Engineers Medal, LT Campbell-Pitt Award, Literati Award, Chairman’s Award of the South African Institute of Air-conditioning and Refrigeration, and Will Stoecker award. He is a member or fellow of various professional institutes and societies such as ASME, ASHRAE, AIAA, and the Royal Aeronautical Society. He is at present the vice president of the Assembly for International Heat Transfer Conferences. In 2020 he won the National Science and Technology Forum award for developing large numbers of engineering research graduates of the highest quality.
At the University of Pretoria he received the “Exceptional Achiever Award” for the fifth time and he also won the Vice Chancellor’s Exceptional Supervisor Award in recognition of exceptional achievement in supervision for his high quality work as a supervisor/advisor of graduate students. In 2019 he won the Chancellor’s Award for Research for sustained excellent performance, in recognition of exceptional achievement in research and the associated promotion of the University of Pretoria. He is an A-rated NRF (National Research Foundation) researcher. The NRF rating are allocated based on a researcher's recent research outputs and impact as perceived by national and international peer reviewers. A-rated researchers are unequivocally recognised by their peers as leading international scholars in their respective fields, for the high quality and impact of recent research outputs.
His is a “highly cited researcher” according to the ISI, and ranked among the top 0.1% in engineering. He is on the editorial board of 13 journals and is editor of 7 journals in his field of research. He has (co)authored more than 800 articles, conference papers, book chapters, and patents and has (co)supervised more than 150 research masters and PhD students. He was on the selection committee of the Franklin Institute Awards Programme (one of the world’s oldest (since 1824)) for the Benjamin Franklin Medal. To date, 117 awards of this institute have been honoured with Nobel prizes.