End-wall film cooling technique is an advanced technology which has been employed in modern gas turbines to protect the surface of the end-wall. The sophistication of this technique has allowed an increase in the combustor outlet temperature, resulting in higher engine overall efficiency. Several criteria are used to judge the performance of film cooling; one of them is film cooling effectiveness (ETA) which has been adopted in most of the literature nowadays. In part I of the investigation, we aim to withdraw an overall correlation between film cooling effectiveness and flow conditions and geometric parameters. A lot independent parameters, that could play a role in film cooling performance, are: blowing ratio, cooling mass flow rate, pitch distance, geometry of the hole, injection angle, and inlet to exit hole-area ratio to name a few. But we need to screen some factors out that seem to be more potentially affect the output based on previous experiences (or available literature), or by conducting pilot runs. Due to nature of preliminary investigation in this part I, the authors found that blowing ratio (BR), density ratio (DR), jet inclination angle (α) and hole length-to-diameter ratio (L/D) are more important and are selected as investigated factors. A full design of experiment is then performed and it is worth to note here that typical values are assigned for those less important factors and they are kept constant in the sensitivity analysis. Regression equation is also extracted to predict the spatial average film cooling effectiveness (ETAaa). This investigation is supported by numerical analysis where the solution of the computational domain is performed using FLUENT package [1]. Second order schemes are used to provide the highest accuracy available. The realizable k-ε model (RKE) is integrated in this work with enhanced wall treatment for all its runs. For the baseline case, computational fluid dynamic (CFD) result is compared against actual experimental data where the experimental baseline work was conducted for a row of cylindrical holes on a flat plate at the Center of Advanced Turbine and Energy Research (CATER). Temperature distribution is captured by using the temperature sensitive paint (TSP) technique and the output design parameter is then calculated.

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