Heat Transfer Characteristics of Hydrocarbon Fuel in a Horizontal Small Tube under Different Pressures

摘要

Experiments for heat transfer of a kerosene hydrocarbon fuel in a small horizontal tube have been conducted at subcritical and supercritical pressures. Parameters included the pressure of 2.0-5.0 MPa, mass flux of 822-2466 kg/ (m~2·s) and heat flux up to 1500 kW/m~2. The wall temperature and heat transfer performance at various operating conditions were captured in the experiments. Based on the results, the normal, improved and deteriorated heat transfer characteristics of the fuel were analyzed in detail. The effects of heat flux, pressure and mass flux on the heat transfer were discussed respectively. The heat transfer performed better when working pressure approached critical pressure. The deterioration in the large change of thermophysical properties region didn't occur at supercritical pressures. In the test, the increase of mass flux could enhance the heat transfer. But the effect of the enhancement decreased with mass flux increase. As to the pressure drop characteristics, low pressure and high mass flux both contributed to the increase of flow resistance.