Effect of Channel Curvature for Jet Impinging on Blade Leading Edge

다국어 초록 (Multilingual Abstract)

The characteristics of fluid flow and heat transfer affected by the curvature variation in a jet impinged leading edge channel have been investigated numerically using three-dimensional Reynolds-averaged Navier-Stokes analysis via shear stress transport turbulence model and γ - Re<SUB>θ</SUB> transitional turbulence model. A constant heat flux condition has been applied on the leading edge surface. Jet to leading edge surface distance is constant as three times of jet diameter. The leading edge curved surface curvature is set as variables by the reason of multiple shape of real turbine blade. Results presented in this study include contour of Nusselt number, velocity vector and local Nusselt number distribution along the central line on the leading edge surface. Based on the data above, the average Nusselt number, stagnation Nusselt number along the central line of leading edge and average pressure supplied on each jet are compared between each case. The varied leading edge curved surfaces change the cross flow intensity which influences the impinging jet flow direction. As a result of the phenomenon of jet flow direction change, the heat transfer on the leading edge is influenced significantly. Result indicates that with the decrease of leading edge curved surface diameter, the cross flow effect improves and heat transfer uniformity decreases. In the case of small diameter leading edge, the average heat transfer decrease and the Nusselt value decreases along the streamwise direction due to the crossflow from upstream jet flow. Besides the heat transfer uniformity, the thermal performance comparison is also investigated in this study.

목차 (Table of Contents)

• Abstract
• 1. Introduction
• 2. Numerical Method
• 3. Problem Set Up
• 4. Result and Discussion
• 5. Conclusion
• Reference