Experiments were performed to determine forced convection heat transfer coefficients and friction factor for air flowing in corrugated channel employed in plate heat exchangers. Measurements were performed for two different values of channel height 5 and 10 mm. for a single corrugation angle of 20degrees. The flow rate was varied over the range 1200 less than or equal to Re less than or equal to 4000. The increase of channel height gave rise to a substantial increase both in the fully developed Nusselt number and the friction fact-or but performance considering flow area goodness factor-slightly decreased. (C) 2003 Published by Elsevier Science Ltd.