Volume 7B: Heat Transfer最新文献

{"title":"Effects of Upstream Step Geometry on Axisymmetric Converging Vane Endwall Heat Transfer and Film Cooling at Transonic Conditions","authors":"B. Bai, Zhigang Li, Jun Li, Shuo Mao, W. Ng, Hongzhou Xu, M. Fox","doi":"10.1115/GT2020-16154","DOIUrl":"https://doi.org/10.1115/GT2020-16154","url":null,"abstract":"\u0000 In real gas turbine engines, a gap/step interface commonly exits between upstream of the inlet guide vane endwall and combustor, called upstream endwall misalignment, due to the errors of assembly and the thermal expansion. This endwall misalignment, commonly being presented as the gap/step geometry with different heights, has a significant effect on the endwall heat transfer and film cooling coverage distributions.\u0000 This paper presents a detailed experimental and numerical study on the effects of upstream endwall misalignment (step geometry) on the vane endwall heat transfer and film cooling in a transonic linear turbine vane passage. The experiment measurements were performed in a blowdown wind tunnel at simulated realistic gas turbine operating conditions (high inlet freestream turbulence level of 16%, exit Mach number of 0.85 and exit Reynolds number of 1.7 × 106. Three types of upstream step geometry were tested at design blowing ratio (BR = 2.5) for the same vane profile: I) baseline geometry with zero-step height of ΔH = 0 mm; II) forward-facing step geometry with negative step height of ΔH = −5 mm; III) backward-facing step geometry with positive step height of ΔH = 5 mm. The endwall thermal load and film cooling coverage distributions were measured using transient infrared thermography, being presented as endwall Nusselt number Nu and adiabatic film cooling effectiveness η, respectively.\u0000 Detailed comparisons of experiment measurements with numerical predictions were also presented and discussed for three types of upstream step configurations with ΔH = −5, 0, 5 mm, respectively. The numerical simulations were performed by solving the steady-state Reynolds Averaged Navier Stokes (RANS) with Realizable k-ε turbulence model, based on the commercial CFD solver ANSYS Fluent v.15. The effects of upstream step geometry were numerically studied, at the same design blowing ratio BR = 2.5, by solving the endwall Nusselt number, film cooling effectiveness and secondary flow field for various upstream step heights: three forward-facing step heights (from −8 mm to −3 mm), a baseline step height (0 mm), and four backward-facing step heights (from 3 mm to 10 mm).\u0000 The results show the upstream forward-facing step geometry is beneficial for the endwall thermal load and film cooling, though the improvement is weak for all step heights (less than 10% decrease in endwall heat transfer and less than 10% increase in endwall film cooling). However, the upstream backward-facing step geometry is pernicious for the endwall heat transfer and film cooling, and the influence increases with the increasing upstream backward-facing step height. The backward-facing step geometry obviously alters near endwall flow field, leading to an enhancement (up to 20%) in endwall heat transfer and significant reduction (up to 60%) in endwall film cooling effectiveness.","PeriodicalId":147616,"journal":{"name":"Volume 7B: Heat Transfer","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127094865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Rim Seal Geometries on Aerodynamic Performance and Rotor Platform Cooling in a One-Stage Turbine","authors":"Qiang Zhao, Xing Yang, Z. Feng","doi":"10.1115/GT2020-16076","DOIUrl":"https://doi.org/10.1115/GT2020-16076","url":null,"abstract":"\u0000 Rim seals are used to prevent ingestion of hot gas into turbine rim cavities. As these cavities are not actively cooled, high-pressure air, known as purge flow, is taken from the compressor and introduced beneath the platform to prevent hot gas from penetrating through the gaps between stationary and rotating parts. Meanwhile, the purge flow impacts the aerodynamic performance and provides secondary-order cooling on the rotor platform. In this paper, the effect of four kinds of engine realistic rim seals on flow fields and rotor platform cooling is investigated with constant coolant rate of 1.0% in a one-stage highly-loaded turbine using an unsteady numerical simulation. The numerical simulation is validated by extensive aerodynamic and heat transfer experimental data. Flow fields and film cooling on the rotor platform and turbine overall aerodynamic performance are discussed and compared in detail for four different rim seal geometries at a design condition of mainstream flow. Case 1 is the conventional radial rim seal geometry and is taken as the baseline (radial injection) rim seal geometry for comparisons. Case 2 (with additional cavity) and Case 3 (incline injection) are obtained by modifying the rim seal geometries based on Case 1. In particular, Case 4 (end wall flank flow), a new structure, is proposed to improve film cooling effectiveness on the rotor hub platform. Comparisons among four rim seal geometries show that the new rim seal structure significantly alters the flow structures near the rotor platform by modifying the development and migration of the purge flow and ingestion of hot gas. The highlight is that the new rim seal geometry of Case 4 could double the film cooling effectiveness or even higher, while at the same amount of coolant. Meanwhile, the aerodynamic performance does not decrease obviously than the other rim seal structures.","PeriodicalId":147616,"journal":{"name":"Volume 7B: Heat Transfer","volume":"485 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122172189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of Geometrical Parameters and Reynolds Number on Flat Plate Film Cooling Effectiveness","authors":"S. Rouina, H. Abdeh, A. Perdichizzi, G. Barigozzi, V. Odemondo, L. Abba, M. Iannone","doi":"10.1115/GT2020-14640","DOIUrl":"https://doi.org/10.1115/GT2020-14640","url":null,"abstract":"\u0000 In the present paper the influence of geometrical deviations, related to the manufacturing process or to a different hole positioning over the vane surface, and of coolant Reynolds number on flat plate film cooling through shaped holes are experimentally investigated. Hole geometrical parameters, such as the length of the cylindrical section, hole injection angle, lateral and forward expansion angles were varied and tested for blowing ratio M values between 1.0 and 2.0, also changing the coolant Reynolds number. The dual-luminophore Pressure Sensitive Paint (PSP) technique was used for measuring the adiabatic film cooling effectiveness distribution. Compared with the standard geometry, the V-shaped hole was shown to produce a better thermal protection, especially in the near hole region. Effectiveness is strongly affected by relatively small changes in the hole geometry, like the length of the cylindrical section and the forward expansion angle. A critical coolant Reynolds number was also identified, whose value changes depending on the hole geometry.","PeriodicalId":147616,"journal":{"name":"Volume 7B: Heat Transfer","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130317565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Cylindrical-Hole Shape and Fillet on Flow and Temperature Fields in Vane Cascade With Endwall Film-Cooling","authors":"B. B. Huyssen, G. I. Mahmood","doi":"10.1115/GT2020-14099","DOIUrl":"https://doi.org/10.1115/GT2020-14099","url":null,"abstract":"\u0000 The aerodynamic performances of the cascade can be improved using the filleted blade profile. The non-uniform distributions of the endwall film-cooling flow from the cylindrical coolant holes have prompted the investigations of cascade flow-field employing several variations of the cylindrical coolant hole geometry. While some variants of the cylindrical hole show potential of improved film-cooling effectiveness on the endwall, the aerodynamic performances of the cascade on the other hand suffer. This paper presents results from the measurements of the flow-field and air temperature along a cascade passage that employs filleted vanes and endwall film-cooling using a diffused shape of the cylindrical coolant holes. The experimental results are also presented in the same vane cascade with the endwall film-cooling using the regular cylindrical coolant holes and without the fillet at the vane endwall junction. The diffused coolant hole is a smooth geometric variation of diffused area of the cylindrical hole and diffuses the coolant flow smoothly along the hole axis. The objectives are to investigate the effects of the fillet and new diffused cylindrical hole on the cascade aerodynamic performances. The effects are illuminated through the interactions of the coolant streams with the mainstream. The measurements are obtained in a linear atmospheric cascade employing a two-dimensional vane profile and an inlet Reynolds number of 2.0E+06. The axis of the coolant holes are oriented at 30° to the endwall at inlet from the coolant plenum. The coolant holes are employed both at upstream and inside of the cascade passage. The fillet extends from the leading edge region to half-way of the vane profile. The time-averaged local velocities, total pressures, and air temperatures are measured at different pitchwise planes in the cascade for the different cases at the endwall. The density ratio of the coolant flow to mainstream is about 1.0 for the flow-field measurements and about 0.94 for the temperature measurements. The overall blowing ratio of the film-cooling flow varies between 1.0 and 2.8. The results of the yaw angle deviations of endwall region flow, total pressure loss coefficients, and non-dimensional temperatures are then presented to provide the effects of the fillet and film-cooling hole geometry. The results show the desirable performances of the local distributions and concentrations of the coolant streams, the low flow turning near endwall, and the reduction of total pressure losses are better when the diffused holes are employed without the presence of fillet. With the fillet and diffused cylindrical holes, the aforementioned aerodynamic performances are improved further compared to those for the regular cylindrical coolant holes.","PeriodicalId":147616,"journal":{"name":"Volume 7B: Heat Transfer","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123215557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling Superposition of Flat Plate Film Cooling Under Complicated Conditions Using Recurrent Neural Networks","authors":"Li Yang, Qi Wang, Y. Rao","doi":"10.1115/GT2020-15131","DOIUrl":"https://doi.org/10.1115/GT2020-15131","url":null,"abstract":"\u0000 Film Cooling is an important and widely used technology to protect hot sections of gas turbines. The last decades witnessed a fast growth of research and publications in the field of film cooling. However, except for the correlations for single row film cooling and the Seller correlation for cooling superposition, there were rarely generalized models for film cooling under superposition conditions. Meanwhile, the numerous data obtained for complex hole distributions were not emerged or integrated from different sources, and recent new data had no avenue to contribute to a compatible model. The technical barriers that obstructed the generalization of film cooling models are: a) the lack of a generalizable model; b) the large number of input variables to describe film cooling. The present study aimed at establishing a generalizable model to describe multiple row film cooling under a large parameter space, including hole locations, hole size, hole angles, blowing ratios etc. The method allowed data measured within different streamwise lengths and different surface areas to be integrated in a single model, in the form 1-D sequences. A Long Short Term Memory model was designed to model the local behavior of film cooling. Careful training, testing and validation were conducted to regress the model. The presented results showed that the method was accurate within the CFD data set generated in this study. The presented method could serve as a base model that allowed past and future film cooling research to contribute to a common data base. Meanwhile, the model could also be transferred from simulation data sets to experimental data sets using advanced machine learning algorithms in the future.","PeriodicalId":147616,"journal":{"name":"Volume 7B: Heat Transfer","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134179010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on Film Cooling Performance Improvement of NGV Leading Edge Subject to Distortion Profiles of Low NOx Combustor","authors":"Wenhao Zhang, Zhihao Wang, Zhiduo Wang, Z. Feng","doi":"10.1115/GT2020-15975","DOIUrl":"https://doi.org/10.1115/GT2020-15975","url":null,"abstract":"\u0000 Under the effect of inlet distortion profiles (including hot-streaks, total pressure profiles, and swirling flow angle patterns), the film cooling performance on the leading edge (LE) region of GE-E3 nozzle guide vanes (NGVs) has been numerically investigated in this paper. Firstly, the complicated inlet distortion profiles of a low NOx combustor chamber has been decoupled to single factors to explore the individual and the coupling effects on the film cooling performance of the NGV LE region (Case 1 to Case 4). Then the original and three modified film-hole configurations are compared and discussed under the quasi-real environment (Case 5 to Case 8). The results indicate that total pressure profile tends to draw more coolant toward the midspan and the residual swirl promotes turnover of the cooling film to the other side of NGVs near the enwalls of LE region. Under the combined effects of different distortion profiles, the cooling film is redistributed on the LE region with some area near the stagnation lines with poor coverage. The upwash or downwash of boundary layer fluid caused by the complicated vortex in passages draws the cooling film on NGV surfaces. And this effect will be strengthened or weakened by the injection angles of holes. Finally, the filmhole configuration in Case 8 with counter-inclined film-hole rows arranged along the stagnation lines shows the best film cooling performance, which has positive effects on the decrease of high temperature region induced by hot streak (HS), and results in more uniform temperature distribution.","PeriodicalId":147616,"journal":{"name":"Volume 7B: Heat Transfer","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133133670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental and Numerical Study on the Effects of the Relative Position of Film Hole and Orientation Ribs on the Film Cooling With Ribbed Cross-Flow Coolant Channel","authors":"Bing-ran Li, Cun-liang Liu, Lin Ye, Hui-ren Zhu, Fan Zhang","doi":"10.1115/GT2020-14389","DOIUrl":"https://doi.org/10.1115/GT2020-14389","url":null,"abstract":"\u0000 To investigate the application of ribbed cross-flow coolant channels with film hole effusion and the effects of the internal cooling configuration on film cooling, experimental and numerical studies are conducted on the effect of the relative position of the film holes and different orientation ribs on the film cooling performance. Three cases of the relative position of the film holes and different orientation ribs (post-rib, centered, and pre-rib) in two ribbed cross-flow channels (135° and 45° orientation ribs) are investigated. The film cooling performances are measured under three blowing ratios by the transient liquid crystal measurement technique. A RANS simulation with the realizable k-ε turbulence model and enhanced wall treatment is performed. The results show that the cooling effectiveness and the downstream heat transfer coefficient for the 135° rib are basically the same in the three position cases, and the differences between the local effectiveness average values for the three are no more than 0.04. The differences between the heat transfer coefficients are no more than 0.1. The “pre-rib” and “centered” cases are studied for the 45° rib, and the position of the structures has little effect on the film cooling performance. In the different position cases, the outlet velocity distribution of the film holes, the jet pattern and the discharge coefficient are consistent with the variation in the cross flow.\u0000 The related research previously published by the authors showed that the inclination of the ribs with respect to the holes affects the film cooling performance. This study reveals that the relative positions of the ribs and holes have little effect on the film cooling performance. This paper expands and improves the study of the effect of the internal cooling configuration on film cooling and makes a significant contribution to the design and industrial application of the internal cooling channel of a turbine blade.","PeriodicalId":147616,"journal":{"name":"Volume 7B: Heat Transfer","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124321243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental Study of Full Coverage Film Cooling Effectiveness for a Turbine Blade With Compound Shaped Holes","authors":"Shuai-qi Zhang, Cun-liang Liu, Qi-ling Guo, Dapeng Liang, Fan Zhang","doi":"10.1115/GT2020-15110","DOIUrl":"https://doi.org/10.1115/GT2020-15110","url":null,"abstract":"\u0000 The film coverage of a turbine blade surface is determined by all the film cooling structures. The direct study of full coverage film cooling is relatively rare, especially for related research on turbine blades. In this paper, the pressure-sensitive paint (PSP) measurement technique is used to carry out experiments under different turbulence intensities and mass flux ratios, and the distribution of the film cooling effectiveness on the entire surface is studied in detail. In this study, a basic turbine blade and an improved turbine blade are investigated. The film cooling hole position distribution on the improved blade is the same as that on the basic blade, but the film cooling hole shape on the suction surface and the pressure surface is changed from cylindrical holes to laid-back fan-shaped holes. Both blades have 5 rows of cylindrical holes at the leading edge and 4 rows of film cooling holes on the suction surface and the pressure surface. The leading edge, suction surface, and pressure surface have their own coolant inlet cavities. This kind of design is not only close to the actual working conditions in a flow distribution but also conveniently eliminates the mutual interference caused by the uneven flow distribution between the pressure surface and the suction surface to facilitate the independent analysis of the pressure surface and the suction surface.\u0000 In this paper, the film cooling effectiveness of two kinds of turbine blades under different turbulence intensities and mass flux ratios is studied. The results show that the average cooling effectiveness of the improved blade is much better than that of the basic blade. The laid-back fan-shaped hole rows improve the cooling effectiveness of the suction surface by 60% to 100% and 50% to 120% on the pressure surface. The increase in turbulence intensity will reduce the cooling effectiveness of the blade surface; however, the effect of the turbulence intensity becomes weaker with an increase in the mass flux ratio. Compared with the multiple rows of cylindrical holes, the cooling effectiveness of the laid-back fan-shaped holes is more affected by the turbulence intensity under the small mass flux ratio.","PeriodicalId":147616,"journal":{"name":"Volume 7B: Heat Transfer","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117051802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Implementation of Hole-Pair in Ramp to Improve Film Cooling Effectiveness on a Plain Surface","authors":"S. Hussain, Xin Yan","doi":"10.1115/GT2020-14838","DOIUrl":"https://doi.org/10.1115/GT2020-14838","url":null,"abstract":"\u0000 Film cooling is one of the most critical technologies in modern gas turbine engine to protect the high temperature components from erosion. It allows gas turbines to operate above the thermal limits of blade materials by providing the protective cooling film layer on outer surfaces of blade against hot gases. To get a higher film cooling effect on plain surface, current study proposes a novel strategy with the implementation of hole-pair into ramp. To gain the film cooling effectiveness on the plain surface, RANS equations combined with k-ω turbulence model were solved with the commercial CFD solver ANSYS CFX11.0. In the numerical simulations, the density ratio (DR) is fixed at 1.6, and the film cooling effect on plain surface with different configurations (i.e. with only cooling hole, with only ramp, and with hole-pair in ramp) were numerically investigated at three blowing ratios M = 0.25, 0.5, and 0.75. The results show that the configuration with Hole-Pair in Ramp (HPR) upstream the cooling hole has a positive effect on film cooling enhancement on plain surface, especially along the spanwise direction. Compared with the baseline configuration, i.e. plain surface with cylindrical hole, the laterally-averaged film cooling effectiveness on plain surface with HPR is increased by 18%, while the laterally-averaged film cooling effectiveness on plain surface with only ramp is increased by 8% at M = 0.5. As the blowing ratio M increases from 0.25 to 0.75, the laterally-averaged film cooling effectiveness on plain surface with HPR is kept on increasing. At higher blowing ratio M = 0.75, film cooling effectiveness on plain surface with HPR is about 19% higher than the configuration with only ramp.","PeriodicalId":147616,"journal":{"name":"Volume 7B: Heat Transfer","volume":"178 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123287657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Film Hole Shape and Turbulence Intensity on the Thermal Field Downstream of Single Row Film Holes","authors":"Zheng Zhang, Hui-ren Zhu, Wei-jiang Xu, Cun-liang Liu, Zhuang Wu","doi":"10.1115/GT2020-16113","DOIUrl":"https://doi.org/10.1115/GT2020-16113","url":null,"abstract":"\u0000 A nylon mesh coated with broadband thermochromic liquid crystal was set in different planes perpendicular to the mainstream direction at various locations downstream of the film hole. By the temperature visualization technique, the colorful non-dimensional temperature images on the nylon mesh of cylindrical hole, water-drop hole and dustpan shaped hole at different blowing ratios and turbulence at angle of 30° and 60° were visualized. The visualization experiment visually studied the effects of hole shape, hole inclination angle, blowing ratio and mainstream turbulence on the distribution of the film. The results show that stream-wise diffusion of water-drop hole reduces kidney vortex intensity, making higher attachment of the film of water-drop than that of cylindrical hole, consequently the lateral coverage range of water-drop hole film is wider than that of cylindrical hole film. The lateral diffusion of dustpan shaped hole further reduces the kidney vortex intensity. This obviously increases the film coverage and strengthens the adhesion of film of dustpan shaped hole. Increasing the inclination angle of the hole and the blowing ratio will increase the normal velocity of the jet and increase the thickness of the film. however, increasing inclination angle and blowing ratio will enhance kidney vortex intensity and decrease the film cooling effectiveness. The high turbulent intensity of mainstream will enhance the lateral diffusion of the film and enhance the mixing of the secondary flow and mainstream, so the continuity and uniformity of film are better. However, the intense mix of secondary flow and mainstream results in the non-dimensional temperature of the film drops sharply and the film coverage reduced accordingly.","PeriodicalId":147616,"journal":{"name":"Volume 7B: Heat Transfer","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115592537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}