Numerical Investigation On Flow And Heat Transfer Characteristics Of Impingement Cooling

Impinging jet can effectively improve the local heat transfer coefficient, which is widelyused in hot components cooling of aircraft engine. As an internal cooling method, thegeometry parameters and the flow parameters of impingement cooling has an importantimpact on the heat transfer. You can optimize the cooling structure and improve the coolingefficiency with doing research the factors which affect the cooling efficiency. For thisbackground, the paper studies the flow and heat transfer characteristics of the impingementcooling with the numerical simulation method.The study includes three aspects: First, doing numerical calculation on the examples inliterature to find the pros and cons of different turbulence models, choosing the mostappropriate turbulence model; The second is to use the turbulence model which have beenidentified, take the basic research on heat the transfer and flow characteristics of factors of thejet impingement cooling; Third, designing the turbine cooling structure in the literature,testing the basic research findings in practical engineering cooling.With research on the flow and heat transfer characteristics of impingement cooling, theconclusions are as follows:1. The cooling efficiency of impingement cooling with the cooling flow of both sides isbetter than one side, and the direction of the jet tilt toward the flow; Inclined jet is notconducive to cooling efficiency, and the low-temperature region on the target have led to theoffset; Reducing the jet diameter can effectively enhance the impact of heat, but also willincrease the uniformity of the temperature on target surface.2. With the other conditions unchanged, there is a reasonable range of the hole space andthe jet-to-surface spacing. The sensible choice of the hole spacing ratio should be between4to5.6, and when the jet-to-surface spacing Zn/d=2, the average Nu number reaches itsmaximum value.3. The cooling efficiency of in-line arrangement is better than staggered arrangementwhen the jet-to-surface spacing Zn/d=1and2, and when the jet-to-surface spacing Zn/d=3and4, the cooling efficiency of staggered arrangement is better than in-line arrangement. Inboth cases, the initial transverse flow reduces heat transfer efficiency.4. The cooling efficiency of impingement cooling changes as the Reynolds number increases; The initial transverse flow reduces the heat exchanger efficiency, and the rat isincrease with the flow of the initial transverse flow, at the same time, the direction of thejet tilt toward the offset more obvious.5. The jet impingement cooling could get a great result in turbine blade cooling, alsowould combine with the basic research findings closely, and provide an effective basis for thepractical application.