Predicting stress and creep life in inconel 718 bladedisk. Steady state stress analysis generated to understand the dynamic behavior of the blade. Turbine blades are subjected to stress from centrifugal force turbine stages can rotate at tens of thousands of revolution per minute and fluid forces that can causes failure yielding or creep failure. Using fem, this paper analyzes the startup and shutdown process of a mw steam turbine. In one study, a finite element fe analysis was performed to examine the damage mechanisms of a turbine disc, along with the critical high stresses caused by. Turbine profiles, aerofoil data and profile construction turbomachinery. Zonebased reliability analysis on fatigue life of gh720li. Fatigue of the highstressed structural elements is an. The optimization goals were to improve the disk stress characteristics and to reduce the mass of the disk. Finite element stress analysis of a typical steam turbine. Critical locations such as keyway and dovetail area experienced stress concentration leading to crack initiation. Fatigue stress analysis of the dv2 engine turbine disk. Zhu sp, huang hz, smith r, ontiveros v, he l, modarres m.
Stress concentrations are predictable at this contact region. This study based on a new fracture mechanics parameter is concerned with assessing the integrity of cracked steam turbine disk which operate under startupshutdown cyclic loading conditions. Discussion includes the development of a one dimensional plane stress model, disk parameterization methods, and the implementation of a genetic. This work is aimed to demonstrate the possibilities of ioso optimization technique when used in combination with wellknown commercial software application for the design of modern reallife objects. Burst of rotor disc is one of the catastrophic failure mode of gas turbine engine. Strength analysis of an aircraft turbocompressor engine turbine disc. Geometric specification of models used in 2 d finite element analysis 61. To solve the problem, the finite element analysis of complex geometrical model of the disc blade segment with much physical nonlinearity such as contact and plasticity was carried out.
Pdf fatigue stress analysis of the dv2 engine turbine disk. Stress and deformation of rocket gas turbine disc under. One of the major sources of the stress arising in the turbomachinery blades are the centrifugal and thermal loads acting at any section of the airfoil. Introduction to steam turbine blade a steam turbine is a mechanical device that extracts thermal. An attention in this paper is focused on the stress analysis and the determination of fracture mechanics parameters in low pressure lp turbine rotor discs and on developing analytic expressions for stress intensity factors at the critical location of lp steam turbine disc. Stress analysis of turbine components under spin rig. Therefore, a comprehensive threedimensional finite element study is made of the effect of the critical geometric features and interface conditions in the firtree region of a gas turbine disc upon the structural integrity. As the maximum theoretical stress and maximum analytical stress is well below allowable limit the turbine disk is safe. He has been involved with material related failure analysis. The bladedisk attachment at the firtree joint, in gas turbine engines is one of critical components which can fail due to fretting fatigue. Ruud engineer, applied mathematics and mechanics section technical engineering analysis branch commissioners office, denver, colorado technical information branch denver federal center denver, colorado.
Contact stress analysis and fatigue life prediction of a. Constant circumferential section heat insulated disc rotor steam temp. Finite element technique has been used for the analysis. This document summarizes the development of an integral perturbation solution of the equations governing momentum transport in microchannels between disks of multipledisk drag turbines such as the tesla turbine. Van nimwegen and samuel tepper airesearch manufacturing company torrance, cal i fornia summa rv one of the critical areas in jet engine design is the high pressure turbine fig. Structural and thermal analysis of steam turbine blade using fem ruttala bhargav m. Static stress failure of gas turbine blades made of super alloys. Fracture analysis of turbine disks and computational. Turbine disk with imitation model for simulation of an operation failure. Millwater university of texas at san antonio, san antonio, texas 78249 a methodology is presented and applied that determines the sensitivities of the probabilityoffracture of a gas turbine disk fatigue. Application of probabilistic sensitivities to probabilistic fatigue analysis of gas turbine engine disks r. Jozef cernan, karol semrad, katarina draganova, miroslava cuttova, 2019 fatigue stress analysis of the dv2 engine turbine disk, aircraft engineering and aerospace t echnology, s. Blade failure is a common problem of a steam turbine and its failure inservice results in safety risks, repair cost and non operational revenue losses. The maximum stress and maximum displacement will be observed.
Finite element stress analysis of a typical steam turbine blade. A discretization scheme is outlined for numerical treatment of the resulting boundary integral equations, and it is consequently illustrated by determining the stress distributions of the turbine rotor disk for which a fem stress solution has been furnished by author. Determination of stress intensity factors in low pressure. Design optimization and analysis of a steam turbine rotor. Thermomechanical behaviour of turbine disc assembly in the. This analysis allows a parametric study of turbine performance based on several nondimensional parameters. Pdf stress analysis and life estimation of gas turbine blisk for. Dynamic analysis of a steam turbine blade in computational environment is carried. The structural stress analysis will be conducted in ansys for different speeds of runner ranges from to 5000 rpm, the runner material will be taken as aluminum, nitronic and chromium. In the present study, a lowpressure turbine disc is analyzed for the stress field under mechanical and thermal loading. Deterministic lcf life prediction is performed based on the values of stress and strain for an individual. Causes of failure different failures of blades made from super alloys may be observed during gas turbine plant testing and operation. However, the size of microscopic imperfections is difficult to control.
Zonebased reliability analysis method for a turbine disk concerning uncertainty quantification is introduced in this section. Probabilistic sensitivities for fatigue analysis of. This work is aimed to demonstrate the possibilities of ioso optimization technique when used in combination with wellknown commercial. Any new component must therefore be carefully designed to be able to withstand thermal stresses, vibrations and loads asserted by the fluid rushing. Of interest is a work by zhuang, in which the author describes the investigation concerned with the analysis of crack growth of a. Probabilistic sensitivities for fatigue analysis of turbine. Keywords finite element analysis, airfoil, root, disk, stress analysis. Structural and thermal analysis of steam turbine blade using fem.
Once the turbine disk has a fatigue fracture failure, the highenergy debris will be generated. Performance evaluation of low pressure energy recovery. In order to determine elasticplastic fracture mechanics parameters fullsize stressstrain state. Preliminary finite element analysis of a compressor disk in. Structural and thermal analysis of steam turbine blade. Deterministic lcf life prediction is performed based on the values of stress and strain for an individual zone obtained from the finite element analysis fea. The present paper, therefore, deliberates the burst of rotating turbine disc due to overspeed. Design and analysis of gas turbine rotor blade using finite element method 77 changes in microstructure. Modal analysis of gas turbine rotor component using finite. Optimization of the gas turbine disk computers and structures vol. For reliable operation of a gas turbine, life prediction of the components of the turbine is of prime importance so that the damages can be detected and repaired before it gets problematic. This modification reduced the maximum effective stress to 854 mpa.
The goal was to highlight the stress and deformation distribution to assist in the design of a disc as well as to demonstrate the importance of using finite element fe analysis in simulating an actual design case. Objective of the work the turbine rotor grooves are most rigid elements in high speed steam and gas turbines used in land based and aerospace applications. The results of the stress analysis of turbine components that work in spin rig conditions have not been widely described in literature. In the present work a sector of the blisk bladed disc has been modeled using ansys 11. As it follows from 3d stress analysis the maximum effective stress occurs at the midplane of the disk and is a function of the ratio hub thicknesshole diameter.
Type of meshing used for gas turbine blade during analysis process in ansys16. Experimental investigation of principal residual stress. Stress analysis of a turbine rotor using finite element modeling. The present paper deals with the stress analysis of a typical blade made up of nickel super alloy, which. Fatigue failure result from a combination of steady stress, vibratory stress, and material imperfections. Calculation of thermal stress and fatigue life of mw. This is an important problem for the operators of turbine engines, since it is a significant driver of fatigue damage and failure risk of disks. In this study, the stresses and deformations of a turbine disc were studied. High pressure turbine blade stress analysis robert r. Lifetime prediction for turbine discs based on a modified. The purpose of this study is to improve life prediction of certain components. Thus, the reliability of these blades is very important for the successful operation of a steam turbine. This paper presents the stress analysis of a second stage turbine disc, subjected to spin rig test.
Examine the effect of speed on stress and displacement of. Prior studies have shown that 2d modeling is insufficient for obtaining reliable predictions of stress and strain distribution and 3d fe analysis is mandatory. The present investigation examines an analysis methodology for fretting fatigue in a turbine engine fan disk. Burst strength analysis of gas turbine disc based on. Lprimlife combines the necessary stress analysis and fracture mechanics algorithms with applicable material degradation data to estimate remaining life. For the threethreedimensional model in fig 3, the 16 turbine disc segment is subjected to a combination of. Turbine blade modal analysis abstract modal analysis has been used to identify natural frequencies, damp ing characteristics and mode shapes of wind turbine blades. Pdf purpose the purpose of this study is to improve life prediction of certain components. Any new component must therefore be carefully designed to be able to withstand thermal stresses, vibrations and loads asserted by the fluid rushing through the turbine. Preliminary finite element analysis of a compressor disk. A plastic stress intensity factor approach to turbine disk. Introduction turbine disc assemblies 1the safety of gas turbine engines has always been the. Optimization of turbine disk aimed to mass and stress.
Analysis gets the temperature field and stress field of the tutor,thus we. Of interest is a work by zhuang, in which the author describes the investigation concerned with the analysis of crack growth of a turbine disc under spin rig conditions. This sophisticated software allows owners to rapidly make critical decisions on cracks. Introduction turbine disc assemblies 1the safety of gas turbine. Damage accumulation and growth in service have occurred on the inner surface of slot fillet of key. Hybrid contact stress analysis of a turbine engine blade to. Nonlinear finite element analysis of thermomechanical. If a component fails, the high rotational speeds can result in a complete rupture of the whole turbine.
Similarly flow simulation of turbine assembly done in ansys at constant head of 2m, different. A typical gas turbine disc is modeled and elasticplastic analysis is carried out by linearly increasing the speed. Turbine blades are subjected to stress from centrifugal force turbine stages can rotate at. The fourth stage low pressure compressor lpc disc of the tf30 engine was chosen as the first component for detailed analysis after being identified as a prime candidate for the retirementforcause lifing methodology 1. Turbine disc assemblies tspace university of toronto. Stress and deformation of rocket gas turbine disc under different.
Failure analysis of first and second stage turbine blade first stage visual observation indicates that more than 90% of the first stage blades were damaged. In addition to the rotationai body forces, the thermal state of a turbine disc. Introduction to steam turbine blade a steam turbine is a mechanical device that extracts thermal energy from high temperature and high pressure steam, and converts it into rotary motion. Pdf modal analysis of wind turbine blades the main part of this research is to identify natural frequencies and natural vibration modes of the al 2024 wind turbine blade. Thermomechanical behaviour of turbine disc assembly in the presence of residual stresses luke maricic master of applied science mechanical and industrial engineering university of toronto 20 abstract a comprehensive three dimensional coupled thermomechanical finite element study is. Application of probabilistic sensitivities to probabilistic.
Stress analysis of blade provide feedback, request enhancements, and get help with windturbine computeraided engineering tools. Gas turbine discs are stressed by a combination of centrifugal forces of rotating masses disc, rotor blades, pressure of exhaust gasses from the combustion. Fatigue of the highstressed structural elements is an essential parameter that affects the lifetime of such components. The analysis of stress values that are produced while the turbine is running are the key. The program assists the user in all aspects of turbine blade analysis. Due to rotation, the blade root gets tightened in the rotor grooves and transmit. Three different fe models were developed from a turbine disk with of dimensions.
These debris are unlikely to be contained by the turbine casting, which can threaten the aircraft safety signi. In this paper, the fe technique is used to predict rotational, bending and thermal stresses in turbine discs and blades. In this study, two analyses in the turbine disk of the jet engine during the simulated operating load were performed. The pressure can be as high as 40 bar, and the temperature more than k. Material properties for disk of turbine are as follow. Request pdf residual stress analysis in inconel 718 milled turbine disk residual stress state in turbine disk after machining could affect the life of the disk. Ramakotaiah 2m sudheer kumar 3t ramesh babu 4t ravi teja 1 assoc. Nov 06, 2012 transient stress analysis and fatigue life estimation of turbine blades journal of vibration and acoustics october 2004, vol. The first one was the analysis of the heatinduced stresses using the finite element method. Bayesian framework for probabilistic low cycle fatigue life prediction and uncertainty modeling of. Therefore, their fracture characteristics, including tensile and fatigue characteristics should be clearly understood with respect to microstructures. In the present study, a lowpressure turbine disc is analyzed for.
Stress analysis, finite element method, gas turbine blade, firtree joint. Optimization, stress concentration factor, turbine rotor grooves, maximum principal stress. Hybrid contact stress analysis of a turbine engine blade to disk attachment. Abstract comprehensive two and threedimensional finite element studies are made of the effect of the critical geomevic features and interface conditions in the frtree region of a gas turbine disc upon the resulting thennomechanicd contact stress distribution at the blade disc interface. Residual stress analysis in inconel 718 milled turbine disk. Nastran analysis of a turbine blade and comparison with test and field data. Steam turbine is an important functional part of many applications. Stress analysis and study of firtree assembly of turbine disc. In particular, aviation engines are devices whose failure due to fatigue failure of one of the important components can lead to fatal consequences. Krishna rao school of mechanical engineering reva university, bangalore, karnataka, india abstract in this article, an effort has been made to deal with structural behavior of. Bayesian framework for probabilistic low cycle fatigue life prediction and uncertainty modeling of aircraft turbine disk alloys.
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