Technical Memorandum of National Aerospace Laboratory
巻
189
ページ
23
発行年
1970-12
抄録(英)
In connection with a study on a fuel vaporizer for a gas turbine combustion chamber, the heat transfer coefficient in a short straight tube through which a fuel-air mixture flowed was investigated experimentally. Liquid isooctane was fed into an air stream in a tube, which was 16 mm in diameter and 400 mm in length, and the heat transfer coefficient was calculated according to the enthalpy difference between inlet- and outlet-flow of the tube. There is a maximum value of heat transfer rate when the wall temperature is about the maximum boiling rate point of the fuel. The peak is, however, gradually dissipated as the air flow rate is increased. When the temperature of the tube is high enough, the heat transfer rate is constant and depends only upon the velocity of the air stream in the tube. It was shown that when liquid fuel drops were suspended in the air stream, the heat transfer rate of the tube at high wall temperature could be assumed to be nearly equal to that of the fuel vapor flowing at the same Reynolds number as the air stream in the tube.