Hot-section components of aircraft gas turbine engines are subjected to severe thermal structural loading conditions, especially during the startup and takeoff portions of the engine cycle. The most severe and damaging stresses and strains are those induced by the steep thermal gradients induced during the startup transient. These transient stresses and strains are also the most difficult to predict, in part because the temperature gradients and distributions are not well known or readily predictable and, in part, because the cyclic elastic-viscoplastic behavior of the materials at these extremes of temperature and strain are not well known or readily predictable. A broad spectrum of structures related technology programs is underway to address these deficiencies at the basic as well as the applied level. The three key program elements in the HOST structural analysis program are computations, constitutive modeling, and experiments for each research activity. Also shown are tables summarizing each of the activities

Thompson, Robert L.

English

NASA Technical Reports Server

N8 9 - 1288 1
HOST STRUCTURAL ANALYSIS PROGRAM OVERVIEW
R.L. Thompson
NASA Lewis Research Center
Cleveland, Ohio
Hot-section components of aircraft gas-turbine engines are subjected to severe
thermal-structural loading conditions, especially during the startup and takeoff
portions of the engine cycle. The most severe and damaging stresses and strains are
those induced by the steep thermal gradients induced during the startup transient.
These transient stresses and strains are also the most difficult to predict, in part
because the temperature gradients and distributions are not well known or readily
predictable and, in part, because the cyclic elastic-viscoplastic behavior of the
materials at these extremes of temperature and strain are not well known or readily
predictable.
A broad spectrum of structures-related technology programs is underway to
address these deficiencies at the basic as well as the applied level, with
participation by industry and universities, as well as in-house at NASA Lewis. The
three key program elements in the HOST structural analysis program are computations,
constitutive modeling, and experiments for each research activity. Also shown are
tables summarizing each of the activities. These elements are shown in the
accompanying schedule and figures.
The computations element of the structures program focuses on developing
improved time-varying thermal-mechanical load models for the entire engine mission
cycle from startup to shutdown. The thermal model refinements will be consistent
with those required by the structural code, including considerations of mesh-point
density, strain concentrations, and thermal gradients. Models will be developed for
the engine hot section components namely, the burner liner, turbine vane, and
turbine blade. An automated component-specific geometric modeling capability, which
will produce three-dimensional finite-element models of the components, is another
part of this element. Self-adaptive solution strategies will be developed and
included to facilitate the selection of appropriate elements, mesh sizes, etc. The
development of new and improved, nonlinear, three-dimensional finite elements and
associated structural analysis programs, including the development of temporal
elements with time-dependent properties to account for creep effects in the
materials and component, is another major part of this element.
The second element of the structures program is the development of constitutive
models and their implementations in structural analysis codes. Improved
constitutive modeling methods to improve the prediction of cyclic thermomechanical
viscoplastic material behavior are being developed for both isotropic and
anisotropic materials. The models are being incorporated in nonlinear,
finite-element structural analysis computer programs and will be exercised on
combustor liners, and turbine blades and vanes.
The third element of the structures program is experimentation. Experimental
facilities to aid in developing and verifying theories and models as well as to aid
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in evaluating advanced instrumentation have been constructed at Lewis. These
include the high temperature structures laboratory for testing tubular specimens and
the structural component response test facility for testing plates, cylinders, and
combustor liner segments. Large quality data bases have been generated in the test
facilities. Advanced strain measurement systems have also been evaluated.
Further explanation and details about the three elements in the structures
program mentioned above are given in the Structural Analysis section of this
publication.
2O
STRUCTURAL ANALYSIS ... IT'S ROLE IN HOST
GOAL:
TO DEVELOPAND VALIDATEINTEGRATEDTIME-VARYINGTHERMAL/MECHANICALOADMODELS,COMPONENT.SPECIFIC
AUTOMATEDGEOMETRICMODELINGAND SOLUTIONSTRATEGYCAPABILITIES,ANO AOVANCEDINELASTICANALYSIS
METHODSAND CONSTITUTIVEMOOELS,INCLUDINGPLASTICITYAND CREEPEFFECTS,FORNONLINEAR,ANISOTROPIC,
FINITEELEMENTSTRUCTURALANALYSISANDDESIGNCOMPUTERCOOES.
PROGRAM INTEGRATION PROGRAM ELEMENTS:
_ MATERIALS ° THERMAL/STRUCTURAL DATA
BEHAVIOR Lj_ TRANSFER MODULE
_Y METHODS ° THERMAL/MECHANICAL LOAD/MISSIONTHERMOMECH IC ] _ _ ANAL SIS AND COMPONENT-SPECIFIC STRUCTURAL
[ LOADSMODELING ' l / MODELS
-I FORLIFE PREDICTIONI
"_ STRUCTURALANALYSIS ° 3-D INELASTIC ANALYSIS METHODS
| AND MODELING |
I I I ° CONSTITUTIVE MODELING
LAB SPECIMENTESTS ] ° STRUCTURAL COMPONENT RESPONSE RIGANDMODELVALIDATION I
° HIGH TEMPERATURE STRUCTURES
LABORATORY
_-85_3351
Figure 1
STRUCTURALANALYSIS
PROGRAM
ELEMENT
THERMAL DATA TRANSFER
COMPONENT SPECIFIC
MODELING
3-D INELASTIC ANALYSIS
ISOTROPIC MODEL
DEVELOPMENT
STRUCTURAL COMPONENT
RESPONSE
HIGH-TEMPERATURE
STRUCTURES LAB
MATERIAL BEHAVIOR
TECHNOLOGY
82 83
FISCAL YEAR
84 85
Figure 2
87 88
EXPECTED
RESULT
COMPUTER MODULE LINKING THERMAL
AND STRUCTURAL ANALYSES
COMPONENT-RELATED, TIME VARYING,
THERMAL-MECHANICAL LOAD HISTORY
AND GEOMETRICMODELS
ADVANCED 3-D INELASTIC STRUCTURAL
STRESS ANALYSIS METHODS AND
SOLUTION STRATEGIES
CYCLIC STRUCTURAL ANALYSIS
BURNER STRUCTURAL LIFE
EXPERIMENTS
INTEGRATED EXPERIMENTAL AND
ANALYTICAL RESEARCH
CONSTITUTIVE THEORY AND
MODELING METHODS
21
HOTSECTIONCOMPONENTSREQUIRING
3-D INELASTICANALYSIS
COMBUSTOR LINER TURBINE BLADE TURBINE VANE
CS-85,3293
Figure 3
BIAXIAL CONSTITUTIVE EQUATION DEVELOPMENT
FOR SINGLE CRYSTALS
OBJECTIVE:
DEVELOP AND VERIFY TWO NEW TYPES OF CONSTITUTIVE MODELS IN MULTIAXlAL FORM FOR A REALISTIC
AIRCRAFT ENGINE SINGLE CRYSTAL ALLOY.
GRANT:
UNIVERSITY OF CONNECTICUT (NAG3-512).
APPROACH:
DEVELOPMENT IS DIRECTED TOWARD ANISDTROPICNICKEL BASE SUPERALLOYS FORTURBINE BLADES AND
VANES.
* BIAXIAL CLASSIFICATION EXPERIMENTS, INCLUDING PROPORTIONAL AND NONPORTIONAL LOADS, WILL BE
PERFORMED TO DETERMINE QUALIFICATIONS MATERIAL BEHAVIOR FOR PWA 1480.
• MODEL DEVELOPMENT WILL BE BASED ON A CRYSTALLOGRAPHIC SLIPSYSTEM VIEWPOINT AS WELL AS
A MACROSCOPICCONTINUUM APPROACH.
• HIGH TEMPERATURE BIAXIAL EXPERIMENTS WILL BE CONDUCTEDTO DETERMINE FUNCTIONAL FORMS AND
MATERIAL CONSTANTS.
• COMPLEX MODEL VERIFICATION TESTS, INCLUDING THERMOMECHANICAL TESTS, WILL BE CONDUCTED.
• THE SINGLE CRYSTAL CONSTITUTIVE MODELS WILL BE INCORPORATED IN A FINITE-ELEMENT PROGRAM.
STATUS:
THIRD YEAR OF GRANT.
ACCOMPLISHMENTS:
TWO ANISTROPIC CONSTITUTIVE MODELS FOR PWA 1480 HAVE BEEN DEVELOPED AND INCORPORATED IN A
FINITE ELEMENT CODE.
A HIGH-TEMPERATURE BIAXIAL COMPUTER CONTROLLED TEST CAPABILITY EXISTS AT THE UNIVERSITY OF
CONNECTICUT.
A DATA BASE ON PWA 1480 IS BEING GENERATED.
COMPLEX BIAXIAL VERIFICATION TESTS HAVE BEEN INITIATED.
c0-eE-22331
Figure 4
22
CONTITUTIVE MODELING OF INELASTIC ANISOTROPIC
MATERIAL RESPONSES
OBJECTVE:
DEVELOP A WORKABLE CONSTITUTIVE MODEL THAT PREDICTS THE INELASTIC STRUCTURAL RESPONSES
OF SINGLE-CRYSTAL ALLOYS USED IN GAS TURBINE ENGINE BLADES AND VANES.
GRANT:
UNIVERSITY OF CINCINNATI (NAG3-511)
APPROACH:
• DEVELOPMENT DIRECTED TOWARD ANISTROPIC, NICKEL-BASE SUPER ALLOYS FOR TURBINE BLADES
AND VANES.
• A DATA BASE OF ISOTHERMAL CYCLES UNIAXIAL BEHAVIOR WILL BE OBTAINED FOR RENE N4.
• AN AUTOMATED PROCEDURE (CODE) FOR OBTAINING MATERIAL CONSTANTS WILL BE DEVELOPED.
• THE MODEL WILL BE INCORPORATED IN A NONLINEAR FINITE ELEMENT CODE AND EXCERCISED ON A
TURBINE BLADE PROBLEM.
STATUS:
THIRD YEAR OF GRANT.
ACCOMPLISHMENTS:
• AN ANISTROPtC CONSTITUTIVE MODEL FOR RENE N4 HAS BEEN DEVELOPED AND INCORPORATED IN A
FINITE-ELEMENT CODE.
• A CODE TO DETERMINE THE MATERIAL CONSTANTS FROM EXPERIMENTAL DATA HAS BEEN DEVELOPED.
• A HIGH-TEMPERATURE UNIAXlAL COMPUTER CONTROLLED TEST CAPABILITY EXISTS AT THE UNIVERSITY
OF CINCINNATI
• TESTING TO ESTABLISH A LARGE QUALTIY DATA BASE FOR RENE N4 AT TEMPERATURES OF 1400, 1600,
AND 1800 OFHAS BEEN INITIATED.
CD_6-22324
Figure 5
MULTIAXIAL TEST PROGRAM TO DETERMINE SURFACES
OF CONSTANT CONSTANT INELASTIC STRAIN RATE
AT ELEVATED TEMPERATURE
OBJECTIVE:
PROVIDE HIGH-TEMPERATURE BIAXIAL EXPERIMENTAL DATA TO ASSIST IN THE FORMULATION OF
NONLINEAR CONSTITUTIVE MODELS FOR STRUCTURAL ALLOYS USED IN TURBINE ENGINE HOT-SECTION
COMPONENTS.
INTERAGENCY AGREEMENT:
OAK RIDGE NATIONAL LABORATORY.
APPROACH:
• COMPUTER CONTROLLED BIAXIAL (TENSION TORSION) TESTS AT A TEMPERATURE OF 650 oC ON A
REFERENCE HEAT OF TYPE 316 STAINLESS STEEL WILL BE CONDUCTED.
• REFERENCETESTS ON INCONEL 718 WILL BE CARRIED ON AT 950 oC
• SURFACES OF CONSTANT INELASTIC STRAIN RATE WILL BE GENERATED AND DATA STORED IN A
COMPUTER.
• A HIGH TEMPERATURE BIAXIAL EXTENSOMETER WILL BE EVALUATED.
STATUS:
SECOND YEAR OF AGREEMENT.
ACCOMPLISHMENT:
• EVALUATION OF A HIGH-TEMPERATURE EXTENSOMETER HAS BEEN COMPLETED.
• SURFACES OF CONSTANT INELASTIC STRAIN RATE ARE BEING GENERATED. SOFTWARE FOR STORAGE,
TRANSFER, REDUCTION, AND ANALYSIS OF DATA HAS BEEN DEVELOPED.
CD 88 22323
Figure 6
23
ORIGINAL pAGE IS
OF POOR QUALITY HIGH-TEMPERATURE STRUCTURES LABORATORY
OBJECTIVE:
PROVIDE HIGH-TEMPERATURE UNtAXIAL AND BIAXIAL EXPERIMENTAL DATA ON CYLINDRICAL SPECIMENS
TO ASSIST IN THE FORMULATION, DEVELOPMENT, AND VERIFICATION OF NEW AND IMPROVED CONSTITUTIVE
MODELS AND TO EVALUATE ADVANCED INSTRUMENTATION ISOTROPIC AND ANISOTROPIC.
IN HOUSE
APPROACH:
• COMPUTER CONTROLLED UNIAXIAL AND BIAXlAL (TENSION/TORSION) TEST MACHINES WILL BE USED TO
PROVIDE EXPERIMENTAL DATA.
" RADIOFREQUENCYAND AUDIOFREQUENCY INDUCTION HEATERS WILL BE USED TO HEAT SPECIMENS TO
DESIRED TEMPERATURES.
• DATA WILL BE STORED ON COMPUTERS FOR FUTURE DATA REDUCTION, ANALYSIS, AND DISPLAY.
• LARGE QUALITY DATA BASES, BOTH ISOTHERMAL AND NONISOTHERMAL, WILL BE OBTAINED AND HIGH-
TEMPERATURE BIAXIAL EXTENSOMETERS WILL BE EVALUATED.
STATUS:
COMPLETED FOURTH YEAR.
ACCOMPLISHMENTS:
• GENERATED LARGE QUALITY UNIAXIAL DATA BASE, BOTH CYCLIC ISOTHERMAL AND NONISOTHERMAL,
FOR HASTALLOY-X
• DEVELOPED SOFTWARE FOR DETAILED ANALYSIS OF DATA.
" DEMONSTRATED THAT COMPUTER CONTROLLED BIAXlAL TEST MACHINES FOR HIGH-TEMPERATURE
TESTING ARE OPERATIONAL.
• EVALUATION OF A HIGH-TEMPERATURE BIAXIAL EXTENSOMETER HAS BEEN COMPLETED.
• HIGH-TEMPERATURE TORSIONAL TESTING IN UNDERWAY.
00-SC_2232_
HIGH TEMPERATURE FATIGUE & STRUCTURES LABORATORY
_- HCF-LCF TESTING FACILITIES
\
UNIAXIAL & MULTIAXIAL TESTING FACILITIES
COMPUTER & INSTRUMENTATION SYSTEMS
Figure 8
24
ORIGi6_AL Pf.,.'.,E_t3
OF POOR QUALITY
BENCH TOP RIG
OBJECTIVE:
PROVIDE HIGH-TEMPERATURE EXPERIMENTAL DATA ON FLAT PLATES TO ASSIST ,IN THE DEVELOPMENT AND
VERIFICATION OF NEW AND IMPROVED STRUCTURAL ANALYSIS AND LIFE PREDICTION TOOLS AND TO
EVALUATE ADVANCED INSTRUMENTATION.
IN HOUSE
APPROACH:
• A QUARTZ LAMP HEATING SYSTEM IS USED TO IMPROVE METAL TEMPERATURES SIMILAR TO AN
IN-SERVICE LINER ON 5 BY 8 IN. FLAT PLATES.
• A 2-3 MIN. THERMOANALYSIS SIMULATES A 3-4 HR ENGINE MISSION CYCLE.
• POWER SETTINGS, COOLING AIR FLOW ROLES, AND COOLING TEMPERATURES ARE VARIED TO MATCH A
DESIRED TEMPERATURE HISTORY ON A LIST PLATE.
• ADVANCED TEMPERATURE, DEVELOPMENT AND STRAIN MEASUREMENT SYSTEMS ARE EVALUATED.
• AN AUTOMATED DATA ACQUISITION SYSTEM IS USED TO STORE, REDUCE, AND DISPLAY THE DATA.
STATUS:
COMPLETED FOURTH YEAR.
ACCOMPLISHMENTS:
• DEMONSTRATED THAT TEST RIG IS A VIABLE STRUCTURAL COMPONENT EXPERIMENTAL TOOL,
• INFRARED THERMOVISION SYSTEM HAS PROVIDED TEMPERATURE MAPS OF COOL SURFACE OF TEST
PLATE.
• EVALUATED A UTRC LASER SPECKLEGRAM SYSTEM TO MEASURE STRAINS,
EVALUATED A HIGH-RESOLUTION CAMERA SYSTEM TO MEASURE DISPLACEMENTS.
• PLATE TEMPERATUARES WERE REPEATABLE FROM CYCLE TO CYLE.
• THERMAL/STRUCTURAL ANALYSIS OF PLATES HAVE BEEN PERFORMED.
Figure 9
BENCH.TOPRIG
I
k
Figure i0
25
STRUCTURAL COMPONENT RESPONSE RIG
OBJECTIVE:
PROVIDE HIGH-TEMPERATURE EXPERIMENTAL DATA ON COMBUSTOR LINER SEGMENTS TO ASSIST IN THE
DEVELOPMENT AND VERIFICATION OF NEW AND IMPROVED STRUCTURAL ANALYSIS AND LIFE-PREDICTION
TOOLS, AND TO EVALUATE ADVANCED INSTRUMENTATION
COOPERATIVE NASA LEWIS AND PRATT & WHITNEY EFFORT.
APPROACH:
• A QUARTZ LAMP HEATING SYSTEM tS USED TO IMPOSE METAL TEMPERATURES ON A 20 IN. DIAMETER
TEST LINER SIMILAR TO AN IN-SERVICE LINER.
• A 2-3 MIN THERMAL CYCLE SIMULATES THE TAKEOFF, CRUISE, LANDING, AND TAXI MODES OF A 3-4 HR
ENGINE MISSION CYCLE.
• POWER SETTINGS, COOLING AIRFLOW RATES. AND COOLING AtR TEMPERATURES ARE VARIED TO MATCH
A DESIRED TEMPERATURE HISTORY OF A POINT ON THE TEST LINER.
• BOTH THERMOCOUPLES AND AN INFRARED CAMERA SYSTEM ARE USED TO MEASURE SURFACE METAL
TEMPERATURES.
• DISPLACEMENT MEASUREMENTS AT CRITICAL LOCATIONS ON THE TEST LINER ARE OBTAINED.
• AN AUTOMATED DATA ACQUISITION SYSTEM IS USED TO STORE, REDUCEAND DISPLAY THE DATA.
STATUS:
COMPLETED FOURTH YEAR.
ACCOMPLISHMENTS:
• DEMONSTRATED THAT TEST RIG IS A VIABLE STRUCTURAL COMPONENT EXPERIMENTAL TOOL.
• COMPLETED LISTING OF A CONVENTIONAL COMBUSTOR LINER SEGMENT.
• LINER CRACKING AT THE SEAM WELD WAS OBSERVED AFTER 1600 THERMAL CYCLES.
• TESTING WAS STOPPED AFTER 1800 THERMAL CYCLES DUE TO LARGE LINER DISTORTION.
• RAISING LINER MAXIMUM TEMPERATURE BY IO0OF ACCELERATED DAMAGE.
• LINER TEMPERATURES WERE REPEATABLE FROM CYCLE TO CYCLE
" LARGE QUALITY DATA BASE INCLUDING TEMPERATURE DISPLACEMENT MEASUREMENTS WAS OBTAINED.
• THERMAL STRUCTURAL: ANALYSIS OF THE LINER HAS BEEN PERFORMED.
co-8e-z233o
Figuce II
PAGE IS
QUALITY
STRUCTURALCOMPONENTRESPONSERIG
Figuce 12
26
ORIGINAL FF,GE IS
OF POOR QUALITY
COMBUSTORTESTLINER AFTER1280 THERMALCYCLES
L
Figure 13
THERMAL-TO-STANDARD DATA TRANSFER MODULE
OBJECTIVE:
DEVELOP AN AUTOMATED PROCEDURE FOR EFFICIENT AND ACCURATE TRANSFER OF TEMPERATURES FROM
A HEAT TRANSFER CODETO A STRUCTURAL ANALYSIS CODE.
CONTRACT:
GENERAL ELECTRIC (NAS3-23272).
APPROACH:
DEVELOP A CODE WITH THE FOLLOWING FEATURESAND CAPABILITIES: MODULAR, USER FRIENDLY, DIFFERENT
3D MESH DENSITIES_ BOTH FINiTE-ELEMENT AND FINITE DIFFERENCEHEAT TRANSFER CODES, EFFICIENT 3D
SEARCHAND WEIGHTING ROUTINES, HARD-WIRED THERMAL AND STRUCTURAL CODES, FILES TO EASILYACCESS
OTHER CODES WINDOWING, ALIGNMENT OF HEAT TRANSFER AND STRESS MODES, EXTERIOR STRESS POINT
BY AN OUTSIDE HEAT TRANSFER MODEL, AND ABILITY TO SELECT A TIME SLIP FROM A LARGE TRANSIENT
THERMAL ANALYSIS.
STATUS:
COMPLETED.
ACCOMPLISHMENTS:
• FINAL REPORTS HAVE BEEN COMPLETED.
• OVER 30 USERS HAVE A COPY OF THE CODE FOR USE AND EVALUATION,
• CODE HAS BEEN SENT TO COSMIC.
Figure 14
27
OVERALLPROGRAMSCHEMATICFOR
3-DIMENSIONALTRANCITS(HOST)
HEAT TRANSFER (HT)CODE STRESS CODE
Figure 15
CS-85.3352
COMPONENT-SPECIFICMODELING(HOST)
Figure 16
28
COMPONENT'S SPECIFIC MODELING (COSMO)
OBJECTIVE:
DEVELOP/VERIFY INTERDISCIPLINARY MODELING ANALYSIS METHODS AND REQUISITE COMPUTER CODES
STREAMLINED FOR THREE HOT-SECTION COMPONENTS.
CONTRACTOR:
GENERAL ELECTRIC BUSINESS GROUP (NAS3-23687).
APPROACH:
• AVAILABLE METHODS FOR GAS DYNAMICS, HEAT TRANSFER 3D INELASTIC.
• ANALYSES AND MODELING TECHNIQUES REQUIRED TO COMPUTATIONALLY VALIDATE HOLSECTION
COMPONENT DESIGNS WILL BE MODIFIED.
• EXTENDED AND INTEGRATED INTO A MODULAR COMPUTER CODE (COSMO) VIA A TWO-PHASE
INCREMENTALLY FUNDED CONTRACT.
STATUS:
THE FIRST PHASE (BASE PROGRAM) OF COSMO IS NEAR COMPLETION.
ACCOMPLISHMENTS:
THE THERMODYNAMIC, THERMOCHEMICAL LOAD TRANSFER, AND EXECUTIVE MODULES ARE OPERATIONAL
ON THE LEWIS CRAY COMPUTER.
CD ee- z2332
Figure 17
CONSTITUTIVE MODELING FOR ISOTROPIC MATERIALS
OBJECTIVE:
TO DEVELOP UNIFIED CONSTITUTIVE MODEL FORFINITE-ELEMENT STRUCTURAL ANALYSES OF TURBINE-ENGINE
HOT-SECTION COMPONENTS.
CONTRACTOR:
SOUTHWEST RESEARCH INSTITUTE (NAS3-23925.)
APPROACH:
• DEVELOPMENT IS DIRECTED TOWARD ISOTROPIC, CAST NICKEL-BASE ALLOYS FOR AIR-COOLED TURBINE
BLADES AND VANES.
• A DATA BASE OF CYCLIC UNIAXIAL AND MULTIAXIAL BEHAVIOR WILL BE OBTAINED FOR A BASE MATERIAL
(B1900) AND AN ALTERNATE MATERIAL (MAR M247).
• EFFICIENT METHODS FOR OBTAINING MODEL CONSTANTS WILL BE DEVELOPED.
• MODELS WILL BE INCORPOATED IN FINITE-ELEMENT CODE AND EXERCISED ON A BLADE AIRFOIL PROBLEM.
STATUS:
• THE BASE PROGRAM HAS BEEN COMPLETED.
• AN OPTIONAL PHASE OF THE PROGRAM IS UNDERWAY IN WHICH THE ALTERNATE MATERIAL WILL BE
STUDIED AND MODEL DEVELOPMENT WILL BE EXTENDED TO INCLUDE COATING, GRAN SIZE, AND THERMAL
HISTORY EFFECTS. IF NECESSARY.
ACCOMPLISHMENTS:
• UPDATED VERSIONS OF THE BODNER AND WALKER MODELS, WITH COMPATIBLE NUMERICAL INTEGRATION
SCHEMES WERE INCORPORATEDIN THE MARC CODE.
• THESE WERE EXERCISED IN SIMULATIONS OF A LARGE NUMBER OF CYCLIC TESTS WITH GENERALLY
GOOD RESULTS.
• FOR THE FIRST TIME UNIFIED CONSTITUTIVE MODELS HAVE BEEN APPLIED TO THE CYCLIC STRUCTURAL
ANALYSIS OF AN ENGINE HOT SECTION COMPONENT.
C04_-22329
Figure 18
29
3-D INELASTICANALYSIS (HOST)
Figure 19
THREE-DIMENSIONAL INELASTIC ANALYSIS METHODS FOR
HOT-SECTION COMPONENTS-I
OBJECTIVE:
DEVELOP NEW ANALYTICAL METHODS THAT PERMIT MORE ACCURATE AND EFFICIENT STRUCTURAL ANALYSIS
FOR COMBUSTER LINERS, TURBINE BLADES AND VANES.
CONTRACTOR:
PRATT & WHITNEY.
APPROACH:
PROVIDE A SERIES OF NEW COMPUTER CODESTHAT EMBODY PROGRESSIVELY MORE SOPHISTICATEDANALYSIS
CAPABILITIES BASED ON:
• AN APPROXIMATE MECHANICS OF MATERIALS FORMULATION (MOMM)
• A STATE-OF-THE-ART, SPECIAL FINITE-ELEMENT FORMULATION (MHOST)
• AN ADVANCED TECHNOLOGY BOUNDARY-ELEMENT FORMULATION (BEST3D).
STATUS:
PROGRAM IN FOURTH YEAR.
ACCOMPLISHMENTS:
• COMPUTER CODES GENERATING WIDESPREAD INTEREST IN GOVERNMENT/INDUSTRY/UNIVERSITY SECTORS.
• FIRST USERS WORKSHOP HELD IN JUNE 1985.
• PRELIMINARY VERSIONS DISTRIBUTED FOR EARLY EVALUATION.
• SECOND USERS WORKSHOP ANTICIPATED FOR LATE 1987.
CD-86-22327
Figure 20
30
THREE-DIMENSIONAL INELASTIC ANALYSIS METHODS
FOR HOT SECTION COMPONENTS-II
OBJECTIVE:
DEVELOP IMPROVED ANALYSIS TOOLS THAT ALLOW MORE ACCURATE AND EFFICIENT CHARACTERIZATION OF
THE CYCLIC TIME DEPENDENT PLASTICITY OCCURRING IN HOT-SECTION COMPONENTS.
CONTRACTOR:
GENERAL ELECTRIC.
APPROACH:
PROVIDE A MATRIX OF FINITE-ELEMENT-BASED CODES WITH VARYING SOPHtSITICATION RELATIVE TO
• ELEMENT TYPE FORMULATION
• MATERIAL CONSTITUTIVE MODEL REPRESENTATION SHARING A COMMON EMPHASIS ON EFFICIENT
SOLUTION ALGORITHMS.
STATUS:
PROGRAM COMPLETED.
ACCOMPLISHMENTS:
• CODE EVALUATION UNDERWAY AT LEWIS.
• USERS WORKSHOP ANTICIPATED FOR LATE 1986.
• CODE DISTRIBUTION THROUGH COSMIC ANTICIPATED IN EARLY 1987.
FiEure 21
31



HOST structural analysis program overview

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