The conference proceedings for the 1997 MSC Aerospace Users' Conference are now available on-line in Adobe Acrobat PDF format. (The Adobe Acrobat Reader software is available for free download from Adobe's web site at www.adobe.com.) When printed, these PDF files will produce a better quality image than the one shown on your computer screen. All papers have been categorized by topic.
ABSTRACT: This paper presents development of a procedure to include flight control system dynamics with aeroelasticity in MSC/NASTRAN. The specific application is on flutter analysis of a twin engine propeller aircraft with the yaw damper flight control system ON. The flutter analysis is performed using the PK-method.
The yaw damper transfer functions are introduced into the aeroelastic equations of motion through a combination of EPOINT and TF entries. One of the extra-points represents the rudder deflection resulting from the yaw damper system. The additional generalized unsteady-aerodynamic forces due to this extra-point are provided with down-washes supplied on DMI entries in the Bulk Data.
The analysis results are presented on V-G and V-F diagrams for two configurations, nominal and yaw damper ON.
ABSTRACT: In the design of aircraft, it is important to have an accurate simulation of both the structural characteristics and the aerodynamic characteristics of the vehicle. For static aerodynamic loads, MSC/NASTRAN uses unsteady aerodynamics at zero reduced frequency. To utilize the accurate structural representation of MSC/NASTRAN in the computation of aeroelastic loads, it is desirable to incorporate aerodynamic and aeroelastic data into the MSC/NASTRAN solution sequence that better represents the actual geometry of the vehicle. This entails importing data that replaces or augments the unsteady data. The Boeing Company, in conjunction with MSC personnel, has prototyped an interface procedure that allows the static aeroelastic loads computations in MSC/NASTRAN to use the rigid aerodynamic forces and aeroelastic corrections from the A502 High Order Panel Method.
ABSTRACT: The MSC.Software Corporation (MSC) developed an aeroelastic analysis and design capability in the late 1970®s and 1980's as part of MSC/NASTRAN. This capability includes flutter analysis, gust analysis and flight loads calculations. The latter is more suited to preliminary and conceptual design. As aerospace companies move to simulate the aeroelastic behavior of the vehicle early in the design cycle, however, there is a need to augment these capabilities to better fit within the current design processes. This augmentation includes new system architecture concepts, enhanced data management and model management and integrated visualization tools that understand aeroelastic models. Finally, new engineering tools need to be implemented that can better model aeroelastic phenomena at an appropriate level of fidelity for use in both vehicle design and production analysis.
This paper will present the critical requirements of the system as understood from numerous discussions with aerodynamicists, loads analysts, dynamicists and aeroelasticians in the aerospace community. Results from this work-in-progress will be presented where appropriate to illustrate the basic architecture, data flow and usage paradigms and their interaction with the aircraft design process.
CHARACTERIZATION
OF MSC/NASTRAN & MSC/ABAQUS ELEMENTS FOR TURBINE, (Acrobat 379KB)
#2097, 15 pgs.
Lt. Jeff Brown--Air Force Research Lab
ABSTRACT: An accuracy study of MSC/NASTRAN and MSC/ABAQUS three dimensional element types was conducted for turbine engine blade natural frequency analysis. Linear, quadratic, hexahedral, and tetrahedral elements were used with different mesh densities in the frequency and mode shape predictions. These results were compared to bench test data and laser holographic mode shapes. Recommendations are made on the selection of finite element meshes for future analyses.
DEFLECTION
ANALYSIS OF AERO GAS TURBINE STRUCTURE DURING PROTOTYPE DEVELOPMENT,
(Acrobat 525KB) #2197, 10 pgs.
M.Chandrasekaran and K.Ramachandra--Gas Turbine Research Establishment,
Bangalore, INDIA.
FINITE
ELEMENT ANALYSES OF A LAMINATED BLADE RETENTION SYSTEM, (Acrobat 456KB)
#2297, 18 pgs.
Dennis K. McCarthy and Robert T. Fort--McDonnell Douglas Helicopter Systems
ABSTRACT: Design of a helicopter main rotor blade retention system is a challenging problem. This critical system must reliably carry large blade loads while allowing extreme blade motions. Several different methods for blade retention systems are currently in service including laminated metallic stacks (LMS). Due to the lack of precise analytic methods laminated metallic stack systems have historically been developed through test. A methodology, developed by the authors, is presented herein to accurately predict the behavior of a LMS blade retention system. This method uses nonlinear finite element (FE) analysis to predict LMS motions and stresses. Finite element results are interrogated to obtain damage and fatigue life predictions. The analytical results are compared to test data with excellent agreement thus verifying the methodology.
HYDROELASTIC
ANALYSIS OF A RECTANGULAR TANK, (Acrobat 271KB) #2397, 26 pgs.
M.C. Kim and S.S. Lee--The Aerospace Corporation
ABSTRACT: A hydroelastic analysis of a rectangular tank is performed using MSC/NASTRAN. Natural frequencies of slosh modes and hydroelastic modes are evaluated, and are compared with results from other approaches as well as analytical values.
LOCAL
STRESS ANALYSIS OF STIFFENED SHELLS USING MSC/NASTRAN'S SHELL AND BEAM
p-ELEMENTS, (Acrobat 68MB) #4797, 10 pgs.
Sanjay Patel, Claus Hoff, Mark Gwillim--The MSC.Software Corporation
ABSTRACT: In large finite element models of aircraft structures, traditional h-elements give sufficient accuracy for most purposes, for example in vibration analysis. However, for local stress analysis of stiffened shells, h-elements may give inaccurate answers at shell-stiffener connections. The paper shows how to use p-elements at those locations where more accurate stresses are required. P-elements work with the existing h-element mesh. A few modifications of the input are necessary to convert local parts of the model into p-elements. The p-version elements improve local stresses significantly. The increase in accuracy is demonstrated on two examples of stiffened shells.
MSC DEVELOPMENTS
IN AEROELASTICITY, (Acrobat 41KB) #4497, 9 pgs.
Erwin H. Johnson--The MSC.Software Corporation
MSC/SUPERMODEL-
A CAE DATA MANAGEMENT AND ADVANCED STRUCTURAL MODELING SYSTEM, (Acrobat
1.2MB) #4597, 11pgs, color
Greg Sikes--The MSC.Software Corporation
RANDOM
ANALYSIS USING MSC/NASTRAN ISHELL MODULE, (Acrobat 1.5MB) #4897, 13
pgs.
Mohan Barbela--The MSC.Software Corporation
AIRFRAME
WATER IMPACT ANALYSIS USING A COMBINED MSC/DYTRAN - DRI/KRASH APPROACH,
(Acrobat 986KB) #3697, 13 pgs.
Gil Wittlin--Dynamic Response, Inc.
Michael Smith and Ashish Sareen, Ph.D.--Bell Helicopter Textron, Inc.
Marv Richards--Simula Government Products, Inc.
AN EVALUATION
OF SERVICE LIFE ANALYSIS OF METALLIC AIRFRAME STRUCTURE WITH MSC/FATIGUE,
(Acrobat 999KB) #3397, color, 15 pgs.
Mark T. Doerfler--Lockheed Martin Tactical Aircraft Systems
IMPLEMENTATION
OF A FLUID-STRUCTURE INTERACTION FORMULATION USING MSC/NASTRAN, (Acrobat
287KB) #3597, 15 pgs.
S. S. Lee, M. C. Kim, and D. R. Williamson--The Aerospace Corporation
INTEGRATING
ADAMS AND MSC/NASTRAN IN THE DESIGN CYCLE, (Acrobat 569KB) #3497,
14 pgs.
Dave Riesland--Mechanical Dynamics, Inc.
ABSTRACT: In order to bring better products to the market faster and at less cost, aerospace companies around the world are embracing the concept of concurrent engineering at a system level. ADAMS, the world leader in Mechanical System Simulation (MSS), ties together diverse component design and analysis technologies such as Computer Aided Design (CAD) and Finite Element Analysis (FEA) in a single system virtual prototype, providing a more complete understanding of product performance. In short, MSS provides the critical enabling technology for meeting true concurrent engineering goals.
CAD/FEA
INTEGRATION WITH STEP AP209 TECHNOLOGY AND IMPLEMENTATION, (Acrobat
283KB) #1297, 13 pgs.
Keith A. Hunten, P.E.--Lockheed Martin Tactical Aircraft Systems
ABSTRACT: The requirements to share geometric shape and analysis information in a large-scale system, especially composite structures, are essential. An emerging standard, the ISO10300 STEP AP209, has been developed to address the data exchange to the design/analysis/manufacturing process. This paper describes the scope, progress and implementation of this effective standards-based solution.
CREATION
& AUTOMATIC ATTACHMENT OF REDUCED COMPONENT MODELS FOR DYNAMIC ANALYSIS,
(Acrobat 64KB) #1597, 17 pgs.
Ted Rose--The MSC.Software Corporation
EFFICIENT
CALCULATION OF TRANSVERSE STRESSES IN COMPOSITE PLATES, (Acrobat 173KB)
#1497, 17 pgs.
Raimund Rolfes--Institute of Structural Mechanics, DLR, Braunschweig,
Germany
Ahmed K. Noor--Center for Advanced Computational Technology, University
of Virginia, NASA Langley Research Center
Klaus Rohwer--Institute of Structural Mechanics, DLR, Braunschweig, Germany
AN EFFICIENT
AND EXACT SOLUTION FOR RANDOM VIBRATION ANALYSIS USING MSC/NASTRAN.PART
I: WHITE NOISE SPECTRUM, (Acrobat 284KB) #3797, 19 pgs.
E. de la Fuente and J. San Millan--Instituto Nacional de Tecnica, Madrid,
Spain
LANDING
RESPONSE ANALYSIS OF AIRCRAFT WITH STORES USING MSC/NASTRAN, (Acrobat
57KB) #3997, 11 pgs.
Zeng Ning--South West United Machinery Corporation, Chengdu, P.R. China
ABSTRACT: In order to ensure safety flight of aircraft, it is very important to study the landing response analysis of aircraft with stores. Earlier aircraft was considered as a stiff body by reason of its lightweight and large structural stiffness. However, the structure of modern aircraft changes into more and more flexible with increasing of size and use of high strength materials. It would make for more accidents if the elastic effects were neglected for the aircraft. In this paper, the problem was solved successfully by means of generalized dynamic reduction and the large mass method of MSC/NASTRAN. The results in the paper show that the solution technique using MSC/NASTRAN is effective and feasible, which is especially suitable for the solution of the dynamic problem of large-scale structure subjected to base enforce motion.
LINK MESH
MODEL OF AN ELEMENTARY PANEL BAY FOR LINEAR MSC/NASTRAN/PARAMETRIC ANALYSIS
OF STIFFENED SHELLS, (Acrobat 57KB) #4097, 29 pgs.
Steven Basic, MS--Boeing Commercial Airplane Group
MULTI-SPRING
REPRESENTATION OF FASTENERS FOR MSC/NASTRAN MODELING, (Acrobat 322KB) #1397,
13 pgs.
Alexander Rutman, Ph. D,and Joseph Bales-Kogan, M. Sc.--Boeing Commercial
Airplane Group
ABSTRACT: The paper describes a particular modeling approach for 3-dimensional representation of fastener joints developed for MSC/NASTRAN. Different physical properties of plate-fastener systems are analyzed separately and interaction between them is established. Calculations of the system properties are shown, as well as the technique of their application in models. Description of a program automating generation of additional cards required by the method is included. The procedure is illustrated with an example showing both an application of the method and results of FEA based on its implementation.
OPTIMIZATION
OF THE C/SiC THRUST CHAMBER FOR A 400N THRUSTER, (Acrobat 364KB) #3897,
10 pgs.
Georg Fleischmann and Ernst Dieter Sach--Daimler-Benz Aerospace AG
MSC/NASTRAN & MSC/PATRAN Applications
AUTOMATIC
3D MESH GENERATION CONFORMING A PRESCRIBED SIZE MAP, (Acrobat 1.35MB)
#4197, 23 pgs.
Paul Louis George--INRIA, Gamma Project, France
Houman Borouchaki--UTT, GSM-LASMIS, France
INTERFACE
ELEMENTS IN GLOBAL/LOCAL ANALYSIS - PART 2: SURFACE INTERFACE ELEMENTS,
(Acrobat 1.3MB) #4397, 18 pgs.
John E. Schiermeier--The MacNeal-Schwendler Corporation
Jerrold M. Housner and Jonathan B. Ransom--NASA Langley Research Center
Mohammad A. Aminpour--Applied Research Associates, Inc.
Jefferson Stroud-- NASA Langley Research Center
ABSTRACT: When performing global/local analysis, the issue of connecting dissimilar meshes often arises, especially when refinement is performed. One method of connecting these dissimilar meshes is to use interface elements. In the previous Part 1, curve interface elements, implemented in MSC/NASTRAN Version 69 for shell and beam p-element edges, were presented. In the current Part 2, surface interface elements, being implemented in MSC/NASTRAN for solid and shell p-element faces, are presented with examples.
SENSITIVITY
EVALUATION ON SPHERE ATTACHMENT SHEAR STRENGTH, (Acrobat 150KB) #4297,
8 pgs, color
T. E. Wong and H. K. Jew--Hughes Aircraft Company
In the present study, the finite element model was first calibrated by test. Three design parameters were then chosen to evaluate the impact of variation of these parameters on the attachment shear strength. Analysis results indicate that the solder pad size is the most critical parameter affecting this shear strength, and the misalignment between the sphere and the solder pad is the next most critical. Therefore, to effectively improve the attachment shear strength, it is recommended to: (1) Use a larger solder pad; and (2) Minimize the misalignment between the sphere and the mounting solder pad. By implementing only the first recommendation into the current design, i.e., increasing the pad diameter from 0.02 in. to 0.03 in., the attachment shear strength could be improved by 160%.
MSC/PATRAN & Other MSC Products
BATCH
COMPUTING IN CLIENT/SERVER IT-INFRASTRUCTURES USING LSF AND THE MSC/ANALYSIS
MANAGER, (Acrobat 19KB) #3297, 4 pgs.
Klaus-Peter Wessel--Daimler Benz Aerospace Airbus
DESIGN
OF AN INTELLIGENT STRUCTURAL QUALIFICATION ENVIRONMENT USING MSC/PATRAN,
(Acrobat 175KB) #3197, 12 pgs.
N.J. Dullaway and A.J. Morris--Cranfield University, England.
OPTIMIZING
THE ENGINEERING PROCESS AT ROCKETDYNE USING MSC/MVISION, (Acrobat
217KB) #3097, 14 pgs, color
Terry Wong--Boeing North American, Inc.
ABSTRACT: In a market where engineers are increasingly being called upon to consider cost and process cycle times in addition to the technical merits of a design, many companies are beginning to realize the important role that materials play in the design of a part. In order to produce a product in a timely and cost efficient manner, a materials engineer who develops design properties must be able to turn test data into design data quickly and accurately. This data must then be made available to the users in a timely fashion. Merely having an abundance of materials properties data is not sufficient to meet the growing demands of a competitive marketplace. The data must be easily retrieved and easily sorted by the user. There must also be a process which can convert the data to a form that is easily usable by software products and processes, such as Computer Aided Design (CAD) and structural analysis programs.
Faced with the above demands, the Rocketdyne Division of Boeing North American decided to implement a materials properties database to meet the above needs. After taking input from engineers in various processes, reviewing several commercially available software packages and even looking into building our own database, we decided to use MSC/MVISION [1] as our official database. We are in the early stages of the database implementation and have already reaped many benefits from its use, and foresee more benefits once the database becomes part of the routine design-to-production process. The implementation of the materials database has not come without difficulties. This paper will discuss both the benefits that Rocketdyne has experienced and the difficulties that we face in the implementation of a material design properties database.
THE USE OF AUTOMATIC TET MESHING
WITHIN A CONCURRENT ENGINEERING ENVIRONMENT, #2997cr
(Acrobat 7MB, color) or #2997bw (Acrobat 1.44MB,
b&w;), both 15 pgs.
C.P. Griffiths--British Aerospace
ADJOINT
SENSITIVITY ANALYSIS IN MSC/NASTRAN, (Acrobat 322KB) #2897, 12 pgs.
Erwin H. Johnson--The MSC.Software Corporation
BOSS-QUATRO
AND MSC/PATRAN: A NEW GENERATION OF OPEN-ARCHITECTURE MULTIDISCIPLINARY
OPTIMIZATION SOFTWARE, (Acrobat 215KB) #2497, 16 pgs.
Patrick Morelle--SAMTECH s.a.
John Klintworth--MSC Ltd.
ABSTRACT: Today's design in industry is in fact a combination of techniques whose primary goal is to understand the model's behavior. The next step is then to analyze the performance of the model using numerical simulation. Various sequences of trade-off, parametric analysis, sensitivity analysis, are then performed in order to formulate the final optimization problem properly. A basic feature of many design problems is their multi-disciplinary nature. As a result, more and more physical phenomena are being modeled and taken into account in the design problem formulation. This has required the use of more disparate and heterogeneous analysis and simulation software.
For those reasons, Samtech s.a. has developed an open design and optimization architecture: BOSS-QUATTRO. This new software has been applied with success in multi-disciplinary (e.g. fluid/structure) analysis and optimization as well as in parametric studies and Monte Carlo analysis. In particular, a very powerful system has been built by linking the BOSS-QUATTRO system to the MSC/PATRAN environment, providing new capabilities for multi-disciplinary optimization by taking advantage of MSC/PATRAN's existing links to multiple analysis codes.
The BOSS-QUATTRO environment is designed as an application manager: it includes existing analysis chains in arbitrary loops and sequences, and provides new capabilities like parametric studies, Monte-Carlo simulation, sensitivity analysis or optimisation. BOSS-QUATTRO is linked to application programs in a standard way through drivers. This open architecture means that the system is able to exchange information with present and future commercial products as well as with in-house codes. For example, drivers exist for popular commercial software MSC/PATRAN, MSC/NASTRAN, SAMCEF, PRO-ENGINEER and CATIA. In addition, any application using a text file for input and output can be linked through a flexible "neutral" driver.
Within the present paper, two applications developed in the context of a BRITE/EURAM project (MODSYSS, CT94-0590) are presented. The first takes advantage of links between MSC/PATRAN and several analysis codes to perform multidisciplinary analyses on a component. The second links a parametric CAD system to an analysis code to allow full three-dimensional shape optimization. These examples demonstrate the ability to link together disparate commercial software systems to perform effective design optimization.
DETERMINISTIC
DESIGN, RELIABILITY-BASED DESIGN AND ROBUST DESIGN, (Acrobat 78KB)
#2597, 11 pgs.
Wei Wang and Justin (Y.T.) Wu--Southwest Research Institute
Robert V. Lust--General Motors Research & Development Center
NEXT GENERATION
STRUCTURAL OPTIMIZATION TODAY, (Acrobat 1.1MB) #2697, 14 pgs,
color
Craig S. Collier, P.E., Mark Pickenheim, and Phil W. Yarrington--Collier
Research & Development Corporation
ABSTRACT: Characteristics of a next generation software product are presented for a coupled MSC/NASTRAN FEA and structural optimization system. These characteristics include methods for automated structural analysis and optimization such as a statistical approach for determining 'design-to' loads and analytical/numerical 'zooming' for detailed global to local response. Software characteristics include a collection of standard panel and beam concepts, and an object oriented approach to strength and stability failure analyses. These features are provided in a multiproject, multiuser, secure database environment where the Internet standard Virtual Reality Modeling Language (VRML) is used for visual interpretation of results.
NONLINEAR
STRENGTH AND STABILITY ANALYSIS OF A LANDING GEAR COMPONENT, (Acrobat
1.17MB) #2797, 15 pgs.
Andrew Mera--The Boeing Company
HP AND
MSC COLLABORATION ON MSC/SUPERMODEL, (Acrobat 114KB) #697, 6 pgs.
Harvey Ivory--The MSC.Software Corporation
Andrew Page--Hewlett-Packard
MSC AEROSPACE
SOLUTIONS: OPTIMIZING THE DESIGN-TO-CERTIFICATION PROCESS, (Acrobat
1.37MB) #197, 12 pgs.
Ken Blakely--The MSC.Software Corporation
MSC PRODUCT
UPDATE, (Acrobat 1.32MB) #597, 14 pgs., color
Mark Kenyon, Bob Jones, Greg Sikes and Alan Caserio--The MSC.Software
Corporation
PRODUCT
SIMULATION INTEGRATION FOR STRUCTURES, (Acrobat 30KB) #397, 6 pgs.
H. Martin Prather, Jr.--The Boeing Commercial Airplane Group (BCAG)
Raymond A. Amador--The MSC.Software Corporation
ABSTRACT: The Product Simulation Integration (PSI) Structures project is under way in BCAG to reduce costs and cycle time in the design, analysis, and support of commercial airplanes. The objective of the PSI project is to define and enhance the processes, methods, and tools to integrate structural product simulation with structural product definition. This includes automated engineering analysis as an integral component of the product definition. Subprojects have been defined and we are working selected topics toward accomplishing the objectives of the PSI for BCAG Structures. Formalized integration activities have also been identified to support the PSI subprojects through their technology life cycle.
REDEFINING
THE PROCESS OF AIRFRAME FINITE ELEMENT MODEL DEVELOPMENT USING MSC/SUPERMODEL,
(Acrobat 1.37MB) #497, 15 pgs, color
Michael Farley-- Raytheon E-Systems Waco
ABSTRACT: To develop, in less than one year, an MSC/NASTRAN 747SP finite element model from scratch to support the SOFIA (Stratospheric Observatory for Infrared Astronomy) program is an effort requiring significant planning. Model development is facilitated by dividing the airframe structure into submodels enabling parallel development of each submodel within separate MSC/PATRAN databases. Directing this effort requires configuration control and file management to maintain the overall pedigree of the model, which includes section properties, history files, drawings used and assumptions made. This paper discusses how MSC/SuperModel is being used to redefine airframe finite element modeling at Raytheon E-Systems Waco.
STRUCTURAL
ANALYSIS FOR THE 21ST CENTURY, (Acrobat 1.37MB) #297, 14
pgs.
Brian P. Oldfield--British Aerospace
A2100
COMMERCIAL SATELLITES INTEGRATED MECHANICAL ANALYSIS, (Acrobat 235KB)
#1797, 14 pgs.
Vince M. Stephens--Lockheed Martin Missiles & Space
ABSTRACT: The commercial satellite industry drive towards reducing delivery time requires that mechanical analyses implement production line type methodologies. Analysis of multiple satellites is facilitated by augmenting MSC/NASTRAN with software that automates FEM checkout, sorts multiple load case stresses/forces, prepares reduced coupled loads models, and facilitates pre-environmental test analyses.
EFFORTS
TOWARDS AN EFFECTIVE STRUCTURAL DESIGN IN ARIANE 5 STRUCTURES DEVELOPMENT,
(Acrobat 1.03MB) #1697, 14 pgs.
Joaquin Martín--Construcciones Aeronauticas, Madrid, Spain
INTERNATIONAL
SPACE STATION THERMALLY INDUCED SOLAR ARRAY BASE LOADS, (Acrobat 409KB)
#1997, 14 pgs.
Tarun Ghosh--Boeing North American, Inc.
TRANSIENT
ANALYSIS OF THERMAL PROTECTION SYSTEM FOR X-33 VEHICLE USING MSC/NASTRAN,
(Acrobat 619KB) #1897, 10 pgs.
H. Miura, M. Chargin, J. Bowles and T. Tam--NASA Ames Research Center
Dan Chu and Mike Chainyk--MacNeal Schwendler Corporation
ABSTRACT: X-33 is an advanced technology demonstrator aircraft for the reusable launch vehicle (RLV) design. The thermal protection system (TPS) for the X-33 is composed of complex layers of materials to protect internal components, while withstanding severe external temperatures induced by aerodynamic heating during high speed flight. It also serves as the vehicle aeroshell in some regions using a stand-off design. MSC/NASTRAN thermal analysis capability was used to predict transient temperature distribution (within the TPS) throughout a mission, from launch through the cool-off period after landing.
In this paper, a typical analysis model, representing a point on the aircraft where the liquid oxygen tank is closest to the outer mold line, is described. The maximum temperature difference between the outer mold line and the internal surface of the liquid oxygen tank can exceed 1500°F. One dimensional thermal models are used to select the materials and determine the thickness of each layer for minimum weight while insuring that all materials remain within the allowable temperature range. The purpose of working with three dimensional (3D) comprehensive models using MSC/NASTRAN is to assess the 3D radiation effects and the thermal conduction heat shorts of the support fixtures.