Professor of Thermal Engineering, Fellow IMechE and EI, was installed as H.T.S. President for 2023.

Tassos Karayiannis obtained a BSc in Mechanical Engineering from City University and a PhD in heat transfer from the University of Western Ontario. He returned to the UK as a research fellow based at Southampton University moving later, as a British Technology Group Researcher, to City University. Subsequently he joined London South Bank University where he served as the School Head of Research, Head of Division and Head of the Department of Engineering Systems. He moved to Brunel University London in 2005 and was instrumental in setting up the new School of Engineering and Design and later the College of Engineering, Design and Physical Sciences, serving as Deputy Head and Vice Dean. Tassos currently leads the Two-Phase Flow and Heat Transfer Group and directs the Brunel Energy Efficient and Sustainable Technologies Research Centre.

Tassos has carried out fundamental and applied research in a number of single and two-phase heat transfer areas funded by EPSRC, Innovate UK and industry. He is a Member of the Assembly for International Heat Transfer Conferences, Editor, Thermodynamics and Heat Transfer, of the J. Mech. Eng. Sc. Part C, and the Chairman of the UK National Heat Transfer Committee.