Numerical Study of Pressure Effect on Deterioration in Heat Transfer with Supercritical Hydrocarbon Fuel

In order to study the pressure effect on heat transfer deterioration of supercritical hydrocarbon fu- el in vertical tube, numerical method with four component surrogate model of RP-3 and LS low Reynolds turbu- lence model was carried out, buoyancy force and physical properties were focused to analyze mechanism of pres- sure effect, meanwhile comparisons between pipes of diameter 2mm and 10mm were done. The numerical results on wall temperature distribution under various conditions were compared with experimental data and a good agree- ment was obtained. Results of the research suggest that when pressure increase to 5MPa without concerning de- composition and coking, the change of physical properties tends to be gentle, the inhomogeneity of density and specific heat are alleviated, average of specific heat increases as well, which all make heat transfer deteriora- tion alleviated. But in the pipe of diameter 10mm, fluid inside is harder to be heated and temperature difference between pipe wall and pipe axis is up to 300K, which leads to the increase of property inhomogeneity, pressure effect of alleviating heat transfer deterioration is weakened.