Numerical And Experimental Study Of Effusion Cooling Of A Plate With Compact Tiny Holes

The paper reports on 3D numerical and experimental study of the flow and heat transfer of an effusion cooled flat plate with compact tiny holes. In the numerical simulation, the paper firstly studied the effects of different blowing angle α(α≤30°),spacing of holes array and blowing ratio M on the cooling effectiveness of effusion cooled plate with aligned holes of the same porosity. And then, the numerical computation of inclined effusion-cooled flat plate is carried out. The influences of the blowing ratio M, the deflection angle γ of inclined array on the cooling effectiveness and heat transfer coefficient of the hot side are analyzed. Moreover, the heat transfer characteristics of the inclined array models are compared with those of the staggered array models with the same geometry and flow parameters. In the experimental investigation, the infrared thermography technique calibrated with thermocouple under the circumstance of real experiment is used to measure the distribution of surface temperature on the entire test field. The heat transfer coefficient of the hot side is determined with the theoretics of transient heat conduction in the semi-infinite slab and the instantaneous temperature measured by the infrared thermography. The effect of blowing ratio M on the adiabatic cooling effectiveness of the effusion cooled bakelite plate is investigated. Then the distribution of the heat transfer coefficient of the metal plate is studied. The experimental results are compared with those of the numerical simulation. The investigation of this paper reveals the mechanism and characteristic of effusion cooling of flat plate with compact tiny holes, which can provide meaningful ideas for the design of the high effectiveness structure in the future jet engines.