关键词: 超临界态+;煤油;传热;数值计算

Abstract: Flow and heat transfer characteristics of China No.3 aviation kerosene in a heated tube and under supercritical pressure were investigated numerically.A two-layer turbulent model,consisting of RNG k-ε model and Wolfstein one-equation model,was used for the simulation of turbulence.A 10-species kerosene surrogate model and NIST Supertrapp software were applied to obtain thermophysical and transport properties of the Daqing No.3 kerosene at varied temperature.Flow conditions of the current study were listed as following: the inlet pressure was 4 MPa;the inlet temperature was 300 K;the mass flows were set from 0.06 to 0.12 kg/s;the wall heat flux was varied from 300 to 700 kW/m2.Results showed that the kerosene thermophysical and flow properties change significantly as the fuel temperature increases along the tube length,of which Reynolds number increases by at least one magnitude and Prandtl number decreases by one magnitude.The heat transfer coefficient increases at the beginning section of the tube,then it decreases slightly as the wall temperature approaches the pseudo-critical temperature,and after that,the heat transfer coefficient rises again,indicating heat transfer enhancement.The current study indicated that the variation in the heat transfer properties can attribute to the complicated thermophysical characteristics of the supercritical kerosene and the change in the turbulence intensity in the near wall region.

Key words: Supercritical state +;Kerosene;Heat transfer;Numerical calculation