Optimization of the blowing ratio for film cooling on a flat plate

Abstract

Purpose The purpose of this paper is to report the result of a numerical investigation of film cooling performance on a flat plate for finding optimum blowing ratios. Design/methodology/approach Steady-state simulations have been performed, and the flow has been considered incompressible. Calculations have been performed with 3D finite-volume method and the k-e turbulence model. Findings The adiabatic film cooling effectiveness and the effects of density ratio (DR), blowing ratio (M) and main stream turbulence intensity (Tu), coolant penetration, hole incline and diameter are studied. The temperature and film cooling effectiveness contours, centerline and laterally film cooling effectiveness are presented for these cases. Results show that the cases with smaller Tu have better effectiveness. In the console, using the air coolant and in cylindrical hole cases, using CO2 coolant fluid has higher effectiveness. The results indicated that there is an optimum blowing ratio in the cylindrical hole cases to optimize the performance of new gas turbines. Research limitations/implications Investigation of optimum blowing ratio for the convex surfaces and turbine blades is a prospective topic for future studies. Practical implications The motivation of this study comes from several industrial applications such as film cooling of gas turbine components. This research gives the best blowing ratio for receiving maximum cooling effectiveness with minimum coolant velocity. Originality/value This study optimizes the blowing ratio for film cooling on a flat plate.

Numerical investigation on the improved three-hole cooling unit with the trench

“…In this section, the numerical results of round and trenched film-cooling holes, referring Cases 1 and 2, are applied versus the experimental results, conducted by Schmidt (Baldauf et al, 2002) and Lu (Lu et al, 2009), respectively, at the corresponding boundary conditions. k-« models have been proved to have the ability of predicting downstream cooling effectiveness, including standard (An and Liu, 2017;Oguntade et al, 2010;Kelishami and Lakzian, 2017;Zhang and Hassan, 2006), RNG (Bayraktar and Yilmaz, 2011) and realizable k-« model (Oguntade et al, 2013). Besides, Zhang and Hassan (2006) proved that the standard k-« model outperforms k-v , Reynolds-Stress and Spalart-Allmaras turbulence model.…”

Comparison of Efficiency-Based Optimal Load Distribution for Modular SSTs with Biologically Inspired Optimization Algorithms

“…The most effective utilization of a scenario or available circumstances/resources is a stitch in time, considering the current energy situation. Many studies are presented and are under consideration dealing with the optimization of diverse scenarios, from all walks of life [47][48][49][50]. The current study may form a base for comparative efficiency analysis of AC and DC distribution systems with the DC system incorporating the suggested scheme of modular architecture.…”

An LBM-Based Investigation on the Mixing Mechanism of Double Rows Film Cooling with the Combination of Forward and Backward Jets

“…In order to suppress the generation of CVP and weaken the associated undesirable effects, many kinds of active and passive control [8][9][10][11][12][13][14][15][16][17][18] have been proposed. Among the active control methods, the key parameters mainly include jet flow frequency [8,9], intensity of freestream turbulence [10,11], density ratio [11,12], and blowing ratio [13]. As for passive control, geometrical shape of film cooling hole [14][15][16] and geometrical parameters of upstream obstacle [17,18] receive lots of attention.…”