An experimental work is conducted to study heat transfer phenomena of a mixed convection in a (sic) shape channel which is subject to a reciprocating motion. Simultaneously, a numerical calculation is executed to validate the experimental results auxiliarily. Parameters of Reynolds number, frequency and amplitude are considered. The results show that enhancement of heat transfer rate caused by the reciprocating motion is remarkable. Due to the impingement of cooling fluids, the heat transfer rate of the front heat region is still superior to those of the middle and back heat regions. The phenomena of this object are very complicated, and the maximum deviation between the experimental and numerical results is not over 25%. (C) 2009 Elsevier Ltd. All rights reserved.