Experimental Investigation into Influence of TBC Surface Roughness on Heat Transfer Coefficient

摘要

Thermal barrier coating (TBC) surface roughness of gas turbine hot parts changes with increasing operation hours. This change in roughness will exert influence on heat transfer coefficient. The influence of surface roughness change on heat transfer coefficient was experimentally determined using TBCs with four kinds of surface roughness. It depends on Reynold's number (Re). There was clear influence at the test condition, Re=l.68×10{sup}5. The specimen with the roughest surface has biggest heat transfer coefficient. On the other hand, there is no big difference at the condition, Re=8.8×10{sup}4.