Download or read book Experimental Investigations of Platform Film Cooling in Highly Loaded Turbine Vanes written by Martin Kunze and published by . This book was released on 2013-12-11 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental Study of Film Cooling and Heat Transfer on a Gas Turbine Vane with Shaped Holes written by Tarek Elnady and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Film Cooling Effectiveness on a Turbine Vane in Transonic Conditions written by Isabella Gayoso and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this experiment, measurements of the overall cooling effectiveness for a film cooled turbine vane airfoil in a high-speed cascade were obtained using infrared thermography. The vane used was the NASA C3X with impingement holes (showerhead cooling) and convective cooling holes on both the suction and pressure side. This work was done in the Mechanical Engineering Department's Experimental and Computational Convection Lab and used the high-speed cascade capability of the lab. The rationale for conducting this work was to obtain experimental data on film cooling effectiveness in a turbine vane in engine-like conditions at transonic speeds. Previous work has been done at subsonic speeds, but few pieces of literature examine this parameter at transonic speeds. The data can then be used to validate or compare to CFD models and to better understand what happens to the vane temperature distribution during engine operation. This understanding could inform the design of film cooling holes to reduce thermal strain "hot spots" which lead to failure of the vane. The results showed that trends for values of overall film effectiveness were as expected in this experiment, such as increases in blowing ratio correlating to increases in overall film effectiveness. However, the blowing ratios used in this study were not as high as values studied previously, indicating a need for more data on overall film effectiveness at transonic speeds.
Download or read book The Effects of Leading Edge and Downstream Film Cooling on Turbine Vane Heat Transfer written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-07-23 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: The progress under contract NAS3-24619 toward the goal of establishing a relevant data base for use in improving the predictive design capabilities for external heat transfer to turbine vanes, including the effect of downstream film cooling with and without leading edge showerhead film cooling. Experimental measurements were made in a two-dimensional cascade previously used to obtain vane surface heat transfer distributions on nonfilm cooled airfoils under contract NAS3-22761 and leading edge showerhead film cooled airfoils under contract NAS3-23695. The principal independent parameters (Mach number, Reynolds number, turbulence, wall-to-gas temperature ratio, coolant-to-gas temperature ratio, and coolant-to-gas pressure ratio) were maintained over ranges consistent with actual engine conditions and the test matrix was structured to provide an assessment of the independent influence of parameters of interest, namely, exit Mach number, exit Reynolds number, coolant-to-gas temperature ratio, and coolant-to-gas pressure ratio. Data provide a data base for downstream film cooled turbine vanes and extends the data bases generated in the two previous studies. The vane external heat transfer obtained indicate that considerable cooling benefits can be achieved by utilizing downstream film cooling. The data obtained and presented illustrate the interaction of the variables and should provide the airfoil designer and computational analyst the information required to improve heat transfer design capabilities for film cooled turbine airfoils. Hylton, L. D. and Nirmalan, V. and Sultanian, B. K. and Kaufman, R. M. Unspecified Center EQUIPMENT SPECIFICATIONS; FILM COOLING; HEAT TRANSFER; LEADING EDGES; STRUCTURAL DESIGN; VANES; AIRCRAFT ENGINES; CASCADE FLOW; DATA PROCESSING; GAS TURBINES; HIGH TEMPERATURE; PARAMETERIZATION; TWO DIMENSIONAL FLOW...
Download or read book Experimental Investigation of Air Film Cooling Applied to an Adiabatic Wall by Means of an Axially Discharging Slot written by S. Stephen Papell and published by . This book was released on 1959 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental and Computational Investigation of Film Cooling on a Large Scale C3X Turbine Vane Including Conjugate Effects written by Thomas Earl Dyson and published by . This book was released on 2012 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study focused on the improvement of film cooling for gas turbine vanes using both computational and experimental techniques. The experimental component used a matched Biot number model to measure scaled surface temperature (overall effectiveness) distributions representative of engine conditions for two new configurations. One configuration consisted of a single row of holes on the pressure surface while the other used numerous film cooling holes over the entire vane including a showerhead. Both configurations used internal impingement cooling representative of a 1st vane. Adiabatic effectiveness was also measured. No previous studies had shown the effect of injection on the mean and fluctuating velocity profiles for the suction surface, so measurements were made at two locations immediately upstream of film cooling holes from the fully cooled cooling configuration. Different blowing conditions were evaluated. Computational tools are increasingly important in the design of advanced gas turbine engines and validation of these tools is required prior to integration into the design process. Two film cooling configurations were simulated and compared to past experimental work. Data from matched Biot number experiments was used to validate the overall effectiveness from conjugate simulations in addition to adiabatic effectiveness. A simulation of a single row of cooling holes on the suction side also gave additional insight into the interaction of film cooling jets with the thermal boundary layer. A showerhead configuration was also simulated. The final portion of this study sought to evaluate the performance of six RANS models (standard, realizable, and renormalization group k-[epsilon]; standard k-[omega]; k-[omega] SST; and Transition SST) with respect to the prediction of thermal boundary layers. The turbulent Prandtl number was varied to test a simple method for improvement of the thermal boundary layer predictions.
Download or read book Film Cooling on the Pressure Surface of a Turbine Vane written by James W. Gauntner and published by . This book was released on 1977 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Film-cooling-air ejection from the pressure surface of a turbine vane was investigated, and experimental data are presented. This investigation was conducted in a four-vane cascade on a J75-size turbine vane that had a double row of staggered holes in line with the primary flow and located downstream of the leading edge region. The results showed that: (1) the average effectiveness of film-convection cooling was higher than that of either film cooling or convection cooling separately; (2) the addition of small quantities of film-cooling air always increased the cooling effectiveness relative to the zero-injection case; however, (3) the injected film must exceed a certain threshold value to obtain a beneficial effect of film cooling relative to convection cooling alone.
Download or read book Experimental Investigation of Overall Effectiveness and Coolant Jet Interactions on a Fully Cooled C3X Turbine Vane written by John W. McClintic and published by . This book was released on 2013 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study focused on experimentally measuring the performance of a fully cooled, scaled up C3X turbine vane. Experimental measurements focused on investigating row-to-row interactions of coolant jets and the contributions of external film cooling and internal impingement cooling to overall cooling effectiveness. Overall effectiveness was experimentally measured using a thermally scaled, matched Biot number vane model featuring a realistic internal impingement scheme and had normalized surface temperatures that were representative of those found on engine components. A geometrically identical vane was also constructed out of low conductivity polystyrene foam to measure the normalized adiabatic wall temperature, or adiabatic effectiveness of the film cooling configuration. The vanes featured a full coverage film-cooling scheme with a five-row showerhead and 13 total rows of holes containing 149 total coolant holes. This study was the first study to make highly detailed measurements of overall effectiveness on a fully-cooled vane model and expands on previous studies of adiabatic and overall effectiveness on the showerhead and single rows of holes on a matched Biot vane by considering a fully cooled configuration to determine if the results from these previous studies also hold for a fully cooled configuration. Additionally, velocity and thermal fields were measured just upstream of two different suction side rows of holes in order to study the effect of introducing upstream coolant injection. The effects of mainstream turbulence and span-wise location were examined and at the downstream row of holes, the contributions of different rows of holes to the approach flow were compared. This study was the first to measure mean and fluctuating velocity data on the suction side of a turbine vane with upstream coolant injection. Understanding the effects of how upstream injection affects the performance of downstream rows of holes is critical to understanding the film cooling performance on a fully cooled turbine airfoil.
Download or read book An Experimental Investigation of the Film cooling Process at High Temperatures and Velocities written by T. Hansmann and published by . This book was released on 1993 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stagnation Region Gas Film Cooling Spanwise Angled Coolant Injection written by David W. Luckey and published by . This book was released on 1976 with total page 357 pages. Available in PDF, EPUB and Kindle. Book excerpt: This experimental investigation involved the study of gas film cooling from a single row of spanwise angled holes using the stagnation region of a cylinder in cross flow to model the leading edge of a turbine vane. The objective was to obtain data for the local convective heat transfer rates to a highly cooled, curved surface exposed to a turbulent hot mainstream flow and a secondary, film coolant flow. Since the leading edge of the first stage, inlet turbine vane experiences some of the most severe thermal loads found in the turbine engine, effective film cooling is most important in this area. Film cooling of the leading edge area was modeled by making heat transfer measurements on the front stagnation region of a cylinder in cross flow. Experiments were conducted in a rectangular duct using a film cooled cylindrical test surface normal to a two-dimensional freestream flow. A gas turbine combustor provided heated air flow to simulate a Reynolds number typical of a high pressure, high temperature turbine vane. Internal convection cooling of the cylinder allowed a gas-to-wall temperature ratio of 2.1 to be achieved while using a moderate freestream gas temperature (1000R; 555K. The film coolant was chilled to obtain a coolant-to-freestream density ratio of 2.2, representative of the gas turbine environment. The cylindrical test surface was instrumented with miniature heat flux gages, and wall thermocouples to determine the influence of the film coolant blowing ratio and the injection hole geometry on the film cooling performance.
Download or read book Variable Incidence Angle Film Cooling Experiments on a Scaled Up Turbine Airfoil Model written by Kyle Feliciano Chavez and published by . This book was released on 2016 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study focused on three main areas of research - the development of a new type of low-speed, closed-loop wind tunnel design to test at varying incidence angles, the investigation of film cooling for gas turbine components at varying incidence angles, and the analysis of the heat transfer and flow field predictive capability of RANS models. In order to develop the closed loop wind tunnel, a rigorous design and validation process was followed. This validated design is unique for low-speed closed-loop facilities. The development of this wind tunnel enabled measurements of adiabatic and overall effectiveness of two highly realistic airfoil models with shaped holes at varying incidence angles. This was accomplished through application of the appropriate aerodynamic and heat transfer scaling parameters for all measurements. Among other results, it was found that the shaped holes at the stagnation row of holes significantly enhanced film cooling effectiveness in the high curvature region of the showerhead depending on the incidence angle tested, and that the incidence angle effect persisted on the matched Biot number model. No previous studies had experimentally investigated the effects of incidence angle effects on overall effectiveness of a full-coverage airfoil. Furthermore, no previous studies had investigated the effect of shaped holes in the showerhead region of a realistic airfoil model such as the one used in this study. Finally, the computational predictive capability of various RANS turbulence models were analyzed by predicting the heat transfer coefficient of the model as well as the turbulence production and turning angle of a vertical array of rods used to generate turbulence in the tunnel. It was found that the computational predictions of leading-edge heat transfer were under-predicted due to the shape of the model leading edge. It was also found that the SST-Transition model appropriately predicted downstream turbulence and turning angle of the vertical rod array when compared to experimental results and empirical correlations in the literature. This is the first study to experimentally and computationally investigate the turning angle of a vertical grid array over a range of zero and non-zero inlet flow angles.
Download or read book Experimental Study of Vane Heat Transfer and Film Cooling at Elevated Levels of Turbulence written by Forrest E. Ames and published by . This book was released on 1996 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Surface Roughness on Local Film Cooling Effectiveness and Heat Transfer Coefficients written by Douglas Neal Barlow and published by . This book was released on 1994 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Analytical and Experimental Investigation of Film Cooling Effectiveness Over a Flat Plate written by Ara Manuel Demirjian and published by . This book was released on 1975 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Papers from the ISABE written by and published by . This book was released on 2005 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On Film Cooling of Turbine Guide Vanes written by Hossein Nadali Najafabadi and published by . This book was released on 2015 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sweeping Jet Film Cooling written by Mohammad Arif Hossain and published by . This book was released on 2020 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gas turbine is an integrated part of modern aviation and power generation industry. The thermal efficiency of a gas turbine strongly depends on the turbine inlet temperature (TIT), and the turbine designers are continuously pushing the TIT to a higher value. Due to the increased freedom in additive manufacturing, the complex internal and external geometries of the turbine blade can be leveraged to utilize innovative cooling designs to address some of the shortcomings of current cooling technologies. The sweeping jet film cooling has shown some promise to be an effective method of cooling where the coolant can be brought very close to the blade surface due to its sweeping nature. A series of experiments were performed using a row of fluidic oscillators on a flat plate. Adiabatic cooling effectiveness, convective heat transfer coefficient, thermal field, and discharge coefficient were measured over a range of blowing ratios and freestream turbulence. Results were compared with a conventional shaped hole (777-hole), and the sweeping jet hole shows improved cooling performance in the lateral direction. Numerical simulation also confirmed that the sweeping jet creates two alternating vortices that do not have mutual interaction in time. When the jet sweeps to one side of the hole exit, it acts as a vortex generator as it interacts with the mainstream ow. This prevents the formation of the counter-rotating vortex pair (CRVP) and allows the coolant to spread in the lateral direction. The results obtained from the low speed at plate tests were utilized to design the sweeping jet film cooling hole for more representative turbine vane geometry. Experiments were performed in a low-speed linear cascade facility. Results showed that the sweeping jet hole has higher cooling effectiveness in the near hole region compared to the shaped hole at high blowing ratios. Next, a detailed experimental investigation of sweeping jet film cooling on the suction surface of a near engine scale transonic nozzle guide vane at an engine relevant Mach number (Ma = 0.8) and Reynolds number (Re = 1x10e6) to determine the effect of compressibility. The heat transfer measurements were conducted with a transient IR method, and the convective heat transfer coefficient (HTC) and adiabatic film cooling effectiveness were estimated using a dual linear regression technique (DLRT). Aerodynamic loss measurements were also performed at an exit plane downstream of the vane cascade. Finally, a comprehensive design integration of sweeping jet film hole was carried out in a Direct Metal Laser Sintering (DMLS) enabled engine scale nozzle guide vane and experimental investigation of overall cooling effectiveness at engine relevant temperature conditions were assessed. The systematic evolution of a sweeping jet film cooling hole design from a large scale flat plate to an engine scale nozzle guide vane has been presented.
