An experimental research was conducted to investigate the level of heat transfer enhancement that can be achieved by corona wind in the developing region of circular tubes. The study was focused on transitional and lower range of turbulent flows with Reynolds number and voltage ranging from 2500 to 13 000 and 0 to 10.5 kV, respectively. The maximum enhancements of the local and average heat transfer coefficients were 14-23% and 6-8%, respectively. These values indicate the level of enhancement beyond the conventional values in the developing region of the circular tubes. (C) 2004 Elsevier Ltd. All rights reserved.