| With the rapid development of the world aviation industry, aerospace engine is gradually upgrading. The current problems the scramjet facing is how to decrease the wall temperature, in order to protect the combustion of the engine. This paper is based on scramjet regenerative cooling techno logy, and it has been verified by a lot of research that porous sintered surface can increase the heat transfer coeffient multiply when the fluid is under boiling conditions. This paper is focused on how the particle size and suspension fluid-solid ratio affect the heat transfer of supercrital aviation kerosene. This research will offer a new method to enhanced heat transfer of supercritical fluid, what’s more, it is of great significance to the regenerative cooling of aviation engine combustionBy comparing the local heat transfer coefficients, the wall temperature at the same axial position and the pressure drop under the same mass flow of the sintered tubes with different parameters, we can make reasonable conclusions about the enhanced heat transfer of aviation kerosene under supercritical pressure.(1) Combared to the smooth tube, the sintered porous tubes can obviously enhance the heat transfer of supercritical aviation kerosene, the wall temperature of the the sintered porous tubes decreases sharply. However, the impact of the particle size is not monotonous, for the tubes, of which the fluid-solid ratio is 0.4, the particle size of 200 mesh is better than that of 150 mesh and 250 mesh.(2) The heat transfer coefficient of supercritical aviation kerosene is increasing gradually with the addition of suspension fluid-solid ratio, and the wall temperature is lower than that of the smooth tubes. Under the same paticle size of 250 mesh, the heat tranfer enhancement reaches thepeak when the suspension fluid-solid ratio is 0.5.(3) The pressure drop of sintered porous tubes is larger than the smooth tube. The change between the particle size and pressure drop is synchronous, but the effect of suspension fluid-solid ratio to the pressure drop is morecomplicated, the pressure drop gets the minimum when suspension fluid-solid ratio is 0.4. However, compared to experimental system pressure drop, pressure drop brought by sintering tube can be negligible.(4) With the guidance of CFD, we analyze the heat transfer characteristics of aviation kerosene and the result indicates:(1) In primary heating process, convective heat transfer is enhanced significantly. (2) When wall temperature surpasses the critical temperature, heat transfer can be deteriorated. (3) When the temperature continues to go up, the convective heat transfer coefficient will rise greatly again. Based on the simulation verification, we go further to analyze how the heat transfer characteristics can be affected by the value of temperature, pressure, heat flux mass velocity and so on, for which we have reached to a few conclusions. |
