Investigation of the Heat Transfer in High Temperature Gas Turbine Vanes (original) (raw)
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2003
The demand for the reduction of aero-engines weight and improvement of fuel consumption remains high for the purpose of reducing CO2. Therefore the turbine blade cooling air of the aero-engines reduces relatively and the turbine specification achieves a high pressure ratio with fewer number of stage i.e. highly-loaded. Advanced cooling technologies applied for high loaded turbines have been earnestly investigated. High performance cooling methods and accurate estimation of heat transfer around airfoils are requested to improve turbine vanes and blades’ life. In this study, high speed cascade tests with typical high loaded transonic turbine vane and blade have been conducted to investigate the flow field, the heat transfer and the film cooling effectiveness around blade surface. NOMENCLATURE A Area C Concentration of a tracer M Mach number or mass flux ratio T Temperature U Velocity p Pressure q Net heat transfer flux Heat transfer coefficient f Film cooling effectiveness Ratio of sp...
Heat transfer and film-cooling for the endwall of a first stage turbine vane
International Journal of Heat and Mass Transfer, 2005
Secondary flows that result in turbomachines from inherent pressure gradients in airfoil passages, are the main contributors to aerodynamic losses and high heat transfer to the airfoil endwalls. The endwalls present a challenge to durability engineers in maintaining the integrity of the airfoils. One means of preventing degradation in the turbine is to film-cool components whereby coolant is extracted from the compressor and injected through small cooling holes in the airfoil surfaces. In addition to film-cooling, leakage flows from component interfaces, such as the combustor and turbine, can provide cooling in localized areas but also provide a change to the inlet boundary condition to the passage. This paper presents measurements relevant to the endwall region of a vane, which indicate the importance of considering the inlet flow condition.
Numerical analysis of effect of thermal performance of gas turbine nozzle guide vane
The present gas turbine engines requires higher entry turbine entry temperatures as engines are operating at higher thrust and thermal efficiency at the same time by operating a turbine at higher temperature reduces the life of blades or vanes because of thermal stresses. Sometimes, the turbine entry temperatures may nearly equal to melting point turbine blade material. Therefore, it is required to determine the blades or vanes to a temperature which gives need to cool the blades optimal condition. In typical gas turbine engines nozzle guide vanes are (NGV) endure the highest operating temperatures. There exists a great drive in the turbine industry to increase the turbine entry temperature leading to higher thermal efficiency.A thermal analysis has been carried out to investigate the direction of the temperature flow which is been develops due to the thermal loading. The present work aims to determine a temperature distribution on blade surface. Heat transfer analysis has been carried out to find out the performance and thermal distribution on the existing blade without internal cooling on nozzle guide vane by using CFD code ANSYS CFX. In this work, CFD analysis has been carried out using Reynolds average Navier stokes equations. The analysis was done without cooling channel on the Nozzle Guide Vane and average temperature on the nozzle guide vane surface will be estimated.
2021
This research provides a computational analysis of heat transfer due to micro jet-impingement inside a gas turbine vane. A preliminary-parametric analysis of axisymmetric single jet was reported to better understand micro jet-impingement. In general, it was seen that as the Reynolds number increased the Nusselt number values increased. The jet to target spacing had a considerably lower impact on the heat transfer rates. Around 30% improvement was seen by reducing the diameter to half while changing the shape to an ellipse saw 20.8% improvement in Nusselt value. The numerical investigation was then followed by studying the heat transfer characteristics in a three-dimensional, actual-shaped turbine vane. Effects of jet inclination showed enhanced mixing and secondary heat transfer peaks. The effect of reducing the diameter of the jets to 0.125 mm yielded 55% heat transfer improvements compared to 0.51 mm; the tapering effect also enhanced the local heat transfer values as local veloci...
Effect of Heat Transfer Coefficient on Cooling of Gas Turbine Blades
International Journal of Scientific Research in Science, Engineering and Technology, 2020
Modern gas turbine blades are optimized and designed to work on elevated temperature. Design of blade is carried out with maximum accuracy and aerodynamic shapes. The shape and design of blade will give him an ability to withstand at high temperature. There are different factors which affect the blade performance with respect to the heat and temperature. It is well known that the gas turbine blade working environment and the temperature is very high. It must possess an ability to work efficiently on this temperature. For that purpose, the effective cooling technique must be implemented in the gas turbines. There are several cooling techniques are used is gas turbines. Such as Convection, Film, Transpiration Cooling, Cooling Effusion, Pin Fin cooling Convection, Film, Transpiration Cooling, Cooling Effusion, Pin Fin cooling etc. Heat Transfer coefficient is the important property of gas turbine blade material, as it affects the thermal performance. To work efficiently, heat must transfer rapidly from the blade. The value of Heat transfer coefficient will decide the heat transfer rate. It is also known that the heat transfer coefficient can affect the thermal conductivity and cooling capacity of material. In this paper the effect of heat transfer coefficient on the cooling capacity is checked out by means of CAD, CAE and CFD tools. CATIA V5R19 and ANSYS 14.5 software are used to carry results. On the basis of results generated further conclusions are drawn.
Numerical heat transfer studies and test rig preparation on a gas turbine nozzle guide vane
2014
Heat transfer study on gas turbine blades is very important due to the resultant increase in cycle thermal efficiency. This study is focused on the heat transfer effects on a reference nozzle guide vane and test rig component preparation in heat and power technology division at KTH. In order to prepare the current test rig for heat transfer experiments, some feature should be changed in the current layout to give a nearly instant temperature rise for heat transfer measurement. The heater mesh component is the main component to be added to the current test rig. Some preliminary design parameters were set and the necessary power for the heater mesh to achieve required step temperature rise was calculated. For the next step, it is needed to estimate the heat transfer coefficient and the other parameters for study on the reference blade using numerical methods. Boundary layer analysis is very important in heat transfer modeling so to model the reference blade heat transfer and boundary ...
Impingement Heat Transfer In The Leading Edge Cavity Of A Gas Turbine Vane
Without their guidance, financial support and help, this work would never have been completed. I'd like to thank them for their belief and faith in me. I am indebted to my project liaisons Dr. Mike Blair and Dr. Jesse Christophel of Pratt and Whitney for their continued support of this project both financially and technically. I would also like to thank my committee member Dr. Muhammad Wahab for his valuable suggestions Last, but not the least, I would like to thank my friends and family for their motivation, support and help.
Heat Transfer Simulation of Gas Turbine Blade with Film Cooling
International Journal of Modern Engineering and Research Technology, 2018
In advance gas turbine, improve the thermal efficiency and power output it is require to increase turbine inlet temperature, that may be exceeds the melting point of the blade material, for that reason blade cooling technique is required. There are several methods have been suggested for cooling of the blades and one of this methods is to have radial holes to pass high velocity cooling air along the blade span. This paper is mainly focus on gas turbine blade heat transfer analysis and effect of increase number of external film cooling holes rows with internal film cooling holes on blade performance and select the optimum design with three different models consist of blade without holes and blades include (2, 3) external rows of film cooling holes with Specific number of internal cooling holes for both last two models. Results have been discussed and it is found that model-2 is the optimum solution, because of maximum total heat transfer rate and reduction in the blade leading edge temperature about 50% are attained in this model compared to model-1 and model-3, and it is found increase number of external film cooling holes rows in the blade not always lowers the blade leading edge temperature, sometimes leads to reheating process this depends on the design location of this holes on the blade surface. Steady state thermal analysis is carried out using CFD, Inconel 718 alloy selection as material and Nitrogen is used as a coolant.
Comparative Analysis of Gas Turbine Blades with and without
2014
In typical gas turbine engines nozzle guide vanes are (NGV) endure the highest operating temperatures. There exists a great drive in the turbine industry to increase the turbine entry temperature leading to higher thermal efficiency. The present gas turbine engines requires higher entry turbine entry temperatures as engines are operating at higher thrust and thermal efficiency at the same time by operating a turbine at higher temperature reduces the life of blades or vanes because of thermal stresses. Sometimes, the turbine entry temperatures may nearly equal to melting point turbine blade material. Therefore, it is required to cool the blades or vanes to a temperature which gives more life to blades or vanes. The present work aims to determine a better internal cooling configuration which gives optimal temperature distribution on blade surface. Conjugate heat transfer analysis has been carried out to find out the performance and thermal distribution on the existing blade with and w...