Abstract: Experiment was carried out to describe the hear transfer coefficient distribution of inner surfaces(target plate,impingement plate and pins) of large scale lamilloy configuration model by utilizing the narrow-band transient iiquid crystal technique(TLC).The mechanism of heat transfer intensification was also interpreted.The result shows that: heat transfer coefficient distribution of inner surfaces of lamilloy can be obtained by using the TLC technique and more detail information are also available;heat transfer coefficient of inner surface is linearly increased with growing Reynolds number and gradually reduced with the higher channel.