Heat Transfer Challenges in Gas Turbine Engine Designs

Hee-Koo Moon, Ph.D., P.E.
Manager, Heat Transfer Development Group
Solar Turbines Incorporated/A Caterpillar Company
San Diego

The gas turbine “jet” engine technology has made a remarkable progress over the last 80 years.  It has brought world community closer and became an essential part of global economy.  The very same technological advances have applied to the industrial version of gas turbine engine, especially to the mid-size industrial gas turbine design.  Brayton (gas turbine) cycle is the thermodynamic cycle that mankind has spent the most amount of resource ever.  The gas turbine engines embody thousands of precisely dimensioned parts  operating  at  close  clearances  with  high  rotational  speeds,  temperatures,  and pressures.  For example, clearances of 5 x 10-5m are maintained between stationary and rotating parts at 0.46 m radius and over 10,000 rpm, in the presence of gas flows at over 30 bars and 1500 oC.  The problems presented in designing such machines for thousands of  hours  of  operation  without  failure  continually  tax  the  most  advanced  skills  and knowledge across an extremely wide range of mechanical and material engineering. The most significant advantage of the gas turbine over other engines is the power density, which is directly proportional to Turbine Inlet Temperature (TIT).  Consequently, single most contribution to the gas turbine technology can be credited to the heat transfer (cooling) technological advance.  The present lecture discusses heat transfer’s role and challenges in the modern gas turbine engine design.

Dr. Hee-Koo Moon is currently Head of the Heat Transfer & Internal Air Systems Group at Solar Turbines Incorporated, a solely owned subsidiary of Caterpillar Company.  He is managing/leading  heat  transfer  engineers  responsible  for  conceptual,  preliminary, detailed heat transfer designs, and experimental/test validation of entire engine thermal systems.  He is also responsible for defining the heat transfer/cooling technology strategy and processes, and for directing advanced heat transfer technology programs at both in-house (company heat transfer laboratory) and universities.  He has co-authored over 130 papers in international journals and conferences (refereed).  He is a fellow of ASME and active in the Heat Transfer Committee of the International Gas Turbine Institute.  He is a co-inventor of 5 patents and 5 more in pending.  Ph.D., M.S., B.S. (with honor) all from Arizona State University.