On the basis of field synergy principle for heat transfer enhancement, physical quantity synergy in laminar flow field of convective heat transfer is analyzed according to physical nature of convective heat transfer between fluid and solid wall. Synergy regulation among physical quantities is revealed by mathematical expressions reflecting mechanism of heat transfer enhancement. Characteristic of heat transfer enhancement, which is directly associated with synergy angles alpha, beta and gamma, is also analyzed. Numerical simulation is made to verify the principle of physical quantity synergy developed in the paper. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.