Experiments were performed to investigate the pressure effect on the heat transfer characteristic of hydrocarbon fuel RP-3 in the horizontal circular tube at supercritical pressures. The mechanisms of heat transfer variation due to the radial thermal property

buoyancy and acceleration effects were discussed as well. The results showed that the heat transfer coefficient increased with the rising fuel bulk temperature. Under different pressures

the fuel thermal property variation's gradient led to the discrepancies of heat transfer and Nux peak points at the same dimensionless bulk temperature. The main reason of the heat transfer distribution was attributable to the radial thermal property gradient due to the temperature discrepancy between the tube inner wall and bulk fuel. However

the buoyancy and acceleration effect were limited in the experiment region. It showed that the dimensionless parameter Grq/Grth precisely reflected the heat transfer characteristic variation of the supercritical hydrocarbon in the horizontal circular tube.