A Numerical Study On The Influence Of Different Structure And Parameters Of Vortex Generators On The Flow And Heat Transfer

Improving the temperature of gas is a good way to improve the power of gas turbine.And the higher temperature of gas means more severe requirement for the material.So it becomes more and more important to devise advanced cooling technique.The main advantage of vortex generator is that it can improve heat transfer greatly without too much pressure loss.So this structure has a bright prospect applied in gas turbine. The main work done in this paper is to explore the flow and heat transfer characteristics in spherical,eliptical,inclined eliptical and teardrop shapes vortex,compare the performance of vortex with ribs with vortex without ribs and explore the influence of ribs’ height on the flow and heat transfer,compare the performance of former rounded and whole rounded spherical vortex with the spherical vortex,investigate the influence of vortex depth on the flow and heat transfer.The numerical results shows that:the teardrop shaped vortex shows the best heat transfer property and the largest pressure lost.Generally speaking,the teardrop shaped vortex still performs best among other shapes votex. The vortex with ribs of one millimeter high can improve the heat transfer by 30%-40% and enhance the friction factor about 80% compared to the spherical votex.The height of ribs has a positive influence on the heat transfer and friction factor.The former rounded spherical vortex shows a slight heat transfer advantage over spherical shapes and its friction factor is much smaller.The all rounded vortex shows the best comprehensive performance owing to its small friction factor.The depth of vortex generally has a postive influence on the heat transfer and higher depth of vortex often means bigger friction factor.The research shows the two millimeters deep votex has the best comprehensive performance.