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    International Journal of Innovative Science and Research Technology
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    — The compressor plays a vital role on jet engine as it concerns about the initial compression on engine bleed system and aircraft cooling. They are two types of compressor used in jet engine. They are axial compressor and centrifugal compressor. Here we discuss about the axial-flow compressor. As its major application were are in large gas turbine engines. This paper investigates the complications over the material selection, and temperature deformation that are majorly induced the stress deformations of blade in operating with different rps of 300 & 450, in the gas turbine engine. For this investigation, NACA6409, NACA64012 airfoils has been selected as base model and these are modelled by using CAD tool CATIA V5 and analysis had been done in ANSYS workbench 16.0, with two various materials viz. Nimonic 80A, Inconel 625.

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    Determination of Thermal Stresses on Turbine Blades

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    — The compressor plays a vital role on jet engine as it concerns about the initial compression on engine bleed system and aircraft cooling. They are two types of compressor used in jet engine. They are axial compressor and centrifugal compressor. Here we discuss about the axial-flow compressor. As its major application were are in large gas turbine engines. This paper investigates the complications over the material selection, and temperature deformation that are majorly induced the stress deformations of blade in operating with different rps of 300 & 450, in the gas turbine engine. For this investigation, NACA6409, NACA64012 airfoils has been selected as base model and these are modelled by using CAD tool CATIA V5 and analysis had been done in ANSYS workbench 16.0, with two various materials viz. Nimonic 80A, Inconel 625.

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    121 views6 pages

    Determination of Thermal Stresses On Turbine Blades

    Uploaded by

    International Journal of Innovative Science and Research Technology
    — The compressor plays a vital role on jet engine as it concerns about the initial compression on engine bleed system and aircraft cooling. They are two types of compressor used in jet engine. They are axial compressor and centrifugal compressor. Here we discuss about the axial-flow compressor. As its major application were are in large gas turbine engines. This paper investigates the complications over the material selection, and temperature deformation that are majorly induced the stress deformations of blade in operating with different rps of 300 & 450, in the gas turbine engine. For this investigation, NACA6409, NACA64012 airfoils has been selected as base model and these are modelled by using CAD tool CATIA V5 and analysis had been done in ANSYS workbench 16.0, with two various materials viz. Nimonic 80A, Inconel 625.

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    © All Rights Reserved
    Download as PDF, TXT or read online from Scribd
    Flag for inappropriate content
    of 6

    Volume 2, Issue 12, December– 2017 International Journal of Innovative Science and Research Technology

    ISSN No:-2456 –2165

    Determination of Thermal Stresses on Turbine Blades


    of Gas Turbine with NACA Airfoils By Finite
    Element Analysis
    Anilkumar Konderu Ganesh Purushothaman
    Dept. of Aerospace Engineer, from HAA Dept. of Aeronautical Engineer
    Affiliated to IGNOU, Delhi Bangalore-37, India
    Bangalore, India

    Abstract— The compressor plays a vital role on jet engine a straight line drawn from the leading edge to the trailing edge
    as it concerns about the initial compression on engine bleed of the airfoil. The blade shape is described by specifying the
    system and aircraft cooling. They are two types of ratio of the chord to the camber at some particular length on
    compressor used in jet engine. They are axial compressor the chord line, measured from the leading edge.
    and centrifugal compressor. Here we discuss about the
    axial-flow compressor. As its major application were are in II. DESIGN OF NACA AEROFOILS
    large gas turbine engines. This paper investigates the
    complications over the material selection, and temperature The airfoils are employed to accelerate and diffuse the air in
    deformation that are majorly induced the stress the jet engines. The nomenclature describes the blade shapes
    deformations of blade in operating with different rps of are almost identical to that of aircraft wings. In most
    300 & 450, in the gas turbine engine. For this investigation, commercial axial flow compressors NACA series blades are
    NACA6409, NACA64012 airfoils has been selected as base used.
    model and these are modelled by using CAD tool CATIA
    V5 and analysis had been done in ANSYS workbench 16.0,
    with two various materials viz. Nimonic 80A, Inconel 625.

    Keywords:-Jet Engine, Turbine Blade, Thermal Stress


    Deformation, NACA6409, NACA64012, Catia V5, Ansys
    Workbench 15.0, Nimonic 80A, Inconel 625.

    I. INTRODUCTION

    The axial flow compressor compresses its working fluid by


    first accelerating the fluid and then diffusing it to obtain a
    resuired pressure increase. The working fluid is accelerated by
    a row of rotating airfoils (blades) called the rotor and then
    diffused (decelerated) in a row of stationary (blades) the
    stators. The axial flow compressor consists of a series of
    stages, each stage comprising a row of rotor blades followed
    by a row of stator blades. The accelerated fluid gains the
    velocity increase in rotor blade and it later passages to stator Fig. 1. Cascade Model of NACA Airfoil
    blade wherein the kinetic energy transferred in the rotor is
    converted to static pressure. A set of one rotor and one stator A. Following Parameters has been Considered for Modelling
    make-up a stage in a compressor. Frontal area in compressor the NACA Airfoils:
    inlet, one additional row of fixed blades called Inlet Guide Inlet pressure: 5bar
    Vanes (IGV) is commonly used to ensure that air enters the
    Mass flow rate: 25kg/sec
    first stage rotors at the desired angle. The last row of stator
    vanes usually act as air straighteners to remove swirl from the Inlet temperature: 1250k
    air to entry into the combustion system.
    Rotational speed (N): 300rev/sec, 450rev/sec
    The blades are curved in design, convex on one side is called Area of annular: 0.0692m2
    suction side of blade and other side concave side is called
    pressure side of the blade. The chord line of an airfoil is Mean blade speed U: 420m/sec
    Um = 2πNrm

    IJISRT17DC176 www.ijisrt.com 393


    Volume 2, Issue 12, December– 2017 International Journal of Innovative Science and Research Technology
    ISSN No:-2456 –2165

    Height of the blade: ρ – Density of material


    AN Acs – constant cross sectional area of blade
    h = rb – distance b/w centre of rotor disc to tip of blade
    U ω – Angular velocity
    Radii of airfoil at root and tip Fc – Centrifugal force acting on per blade

    h h C. Modelling Airfoils in CAD Tool:


    rtip = rm+ ; rroot = rm - By using standard assumptions, theoretical calculations are
    2 2 made to obtain the dimensions of the NACA 6409 & 64012
    Adopting the height to chord (h/c) of 1.28: airfoils and modelled by using cad tool Catia V5 as shown in
    height Fig 2. The design parameters are given in table I.
    = 1.28
    chord

    NACA 6409 & 64012 with different rotational speeds

    Parameters 300rps 450rps


    Height 49.2mm 74.1mm
    rroot 197.4mm 111.4mm
    rtip 246mm 185.5mm
    Chord 38.4mm 57.8mm

    Table 1: NACA 6409 & 64012 with Different Rotational


    Speeds

    Mechanical properties of meaterials


    Fig. 2. NACA Airfoil Model in Catia V5
    Properties Inconel 625 Nimonic 80A
    Density (kg/m3) 8440 8160 III. THERMAL STRESSES BY USING FEA
    Tensile Modulus (mpa) 207500 222000
    The finite element analysis for thermal stress analysis of gas
    Possion’s Ratio 0.3 0.3 turbine engine, rotor blade is carried out by using Ansys 16.0
    Yield Strength (mpa) 448 780 software. Catia models are imported to Ansys workbench for
    simulating the thermal stresses on both NACA airfoils blades,
    Thermal Conductivity 9.8 28.4
    with two different materials at different speeds of 300rev/sec
    (w/m-k)
    and 450rev/sec. Discretization of geometry is done by using
    Ansys meshing workbench, with multizone meshing technique
    Table 2: Mechanical Properties of Materials
    of solid90 elements.
    B. Nomenclature:

    α – Angle of attack
    β – Inlet blade angle
    θ – Camber angle
    c – Chord length
    s – Blade spacing
    z – Position of max camber
    i – Angle of incidence (α1 - β1)
    t – Thickness of blade
    AR – Aspect ratio of blade
    γ – Stagger angle
    h – Height of blade
    rroot – Radius of blade at root
    rtip – Radius of blade at tip
    r m– Radius of mean rotor Fig. 3. Discretizing the Blade Geometry Using Ansys Wb

    IJISRT17DC176 www.ijisrt.com 394


    Volume 2, Issue 12, December– 2017 International Journal of Innovative Science and Research Technology
    ISSN No:-2456 –2165

    A. Boundary Conditions of Rotor Blade:s

    Fig. 6. Heat Flux & Temperature Distribution of NACA


    6409 of Inconel 625 At 450rev/Sec

    Fig. 4. Load Acting Rotor Blade

    Centrifugal force acting on per blade:

    Fc = ρAω2 rb2 – rm2 Fig. 7. Heat Flux & Temperature Distribution of NACA
    2 6409 of Nimonic80A At 300rev/Sec

    RPM * 2π
    ω= rad/sec
    60

    IV. RESULTS
    To determine the thermal stresses, first steady state thermal
    analysis is carried out for acquire temperature distribution and
    heat flux for rotor blade.
    Fig. 8. Heat Flux & Temperature Distribution of NACA
    6409 of Nimonic80A At 450rev/Sec

    Fig. 5. Heat Flux & Temperature Distribution of NACA


    6409 of Inconel 625 At 300rev/Sec Fig. 9. Heat Flux & Temperature Distribution of NACA
    64012 of Inconel 625 At 300rev/Sec

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    Volume 2, Issue 12, December– 2017 International Journal of Innovative Science and Research Technology
    ISSN No:-2456 –2165

    NACA 64012 heat flux (W/mm2)


    Rev/sec Inconel 625 Nimonic 80A
    300 2.6424 8.4396
    450 6.5685 1.4875

    Table 4: NACA 64012 Heat Flux (W/mn2)

    The obtained thermal results are coupled to the static structural


    analysis to acquire the equivalent stresses and displacements,
    with participated centrifugal loads on rotor blade.
    Fig. 10. Heat Flux & Temperature Distribution of NACA
    64012 of Inconel 625 At 450rev/Sec

    Fig. 13. Eqv Stress & Total Deformation of NACA 6409 of


    Fig. 11. Heat Flux & Temperature Distribution of NACA Inconel 625 At 300rev/Sec
    64012 of Nimonic80A At 300rev/Sec

    Fig. 14. Eqv Stress & Total Deformation of NACA 6409 of


    Inconel 625 At 450rev/Sec

    Fig. 12. heat flux & Temperature distribution of NACA


    64012 of Nimonic at 450rev/sec

    NACA 6409 heat flux (W/mm2)

    Rev/sec Inconel 625 Nimonic 80A


    300 3.1522 8.4396
    450 1.3827 1.4875

    Table 3: NACA 6409 Heat Flux (w/mn2) Fig. 15. EQV Stress & Total Deformation of NACA 6409 of
    Nimonic80A At 300rev/Sec

    IJISRT17DC176 www.ijisrt.com 396


    Volume 2, Issue 12, December– 2017 International Journal of Innovative Science and Research Technology
    ISSN No:-2456 –2165

    Fig. 19. Eqv Stress & Total Deformation of NACA 64012 of


    Fig. 16. Eqv Stress & Total Deformation of NACA 6409 of Nimonic 80A at 300rev/sec
    Nimonic80A At 450rev/Sec

    Fig. 20. Eqv Stress & Total Deformation of NACA 64012 of


    Fig. 17. Eqv Stress & Total Deformation of NACA 64012 of
    Nimonic 80A at 450rev/sec
    Inconel 625 At 300rev/Sec

    NACA 6409 at 300rev/sec

    parameters Inconel 625 Nimonic 80A


    Deformations (mm) 0.3609 0.379
    Eqv Stress (MPa) 382.41 538.8

    Table 5: NACA 6409 AT 300rev / sec

    NACA 6409 at 450rev/sec

    parameters Inconel 625 Nimonic 80A


    Deformations (mm) 0.8250 0.7711

    Eqv Stress (MPa) 663.41 663.41


    Fig. 18. EQV Stress & Total Deformation of NACA 64012 of
    Inconel 625 At 450rev/Sec
    Table 6: NACA 6409 at 450rev/sec

    IJISRT17DC176 www.ijisrt.com 397


    Volume 2, Issue 12, December– 2017 International Journal of Innovative Science and Research Technology
    ISSN No:-2456 –2165

    [7]. Meherwan P. Boyce, “Gas Turbine Engineering


    NACA 64012 at 300rev/sec Handbook”.
    parameters Inconel 625 Nimonic 80A
    Deformations (mm) 0.2137 0.1931
    Eqv Stress (MPa) 367.04 354.83

    Table 7: NACA 64012 at 300rev/sec

    NACA 64012 at 450rev/sec


    parameters Inconel 625 Nimonic 80A
    Deformations (mm) 0.6857 0.6196
    Eqv Stress (MPa) 513.05 496.01

    Table 8: NACA 64012 at 450rev/sec

    V. CONCLUSION

    • Both the materials with different rpm and airfoils, are


    given considerable results, but final conclusion can be
    done on the basis of stresses induced in the material.
    • The temperature distribution is depends upon the heat
    transfer coefficient and thermal conductivity of the
    material.
    • From the results we can observe the maximum
    temperature at the root of the blade due to stagnation
    effects at root.
    • Heat flux is marginally lower on NACA 6409 airfoil at
    450rev/sec of Inconel 625 material, because of lower
    thermal conductivity.
    • NACA 64012 airfoil at the speed of 300rev/sec, has
    induced comparatively lesser stress than yield strength of
    the material; with Nimonic 80A material, because of
    young’s modulus of material.
    • More stresses are induced at the blade root, because of,
    blade is cantilever (one end is fixed)
    • From this analysis it is concluded that Nimonic 80A
    material can be used for gas turbine rotor blade.

    REFERNCES

    [1]. Ravi Ranjan Kumar and Prof. K. M. Pandey, “Static


    Structural and Modal Analysis of Gas Turbine Blade” IOP
    Conf. Series: Materials Science and Engineering 225
    (2017) 012102.
    [2]. Win Lai Htwe, Htay Htay Win, Nyein Aye San,
    “DESIGN AND THERMAL ANALYSIS OF GAS
    TURBINE BLADE”, International Journal of Mechanical
    and Production Engineering, ISSN: 2320-2092, Volume-
    3, Issue-7.
    [3]. Theju V1, Uday P S, “Design and Analysis of Gas
    Turbine Blade”, ISSN: 2319-8753, Vol. 3, Issue 6.
    [4]. Prof. Q. H. Nagpurwala, “Design of Axial Flow Turbine-
    1” M S Ramaiah School of Advanced Studies, Bengaluru.
    [5]. Forces on Large Steam Turbine Blades by RWE power.
    [6]. Prof. M. D. Deshpande, “Airfoil design”, M S Ramaiah
    School of Advanced Studies, Bengaluru.

    IJISRT17DC176 www.ijisrt.com 398

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