Nastran

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NASTRAN is a general purpose finite element analysis (FEA) program, originally produced by NASA.

"General purpose" means that Nastran addresses a wide range of engineering problem-solving requirements (i.e. beam versus plate structures and various types of response such as statics or dynamics) as compared to specialty programs, which concentrate on particular types of analysis.

Contents

[edit] History

The 1964 annual review of NASA's structural dynamics research program revealed that the research centers were separately developing structural analysis software that was specific to their own needs. The review recommended that a single generic software program should be used instead. In response, an ad hoc committee was formed. The committee determined that no existing software could meet their requirements. They suggested establishing a cooperative project to develop this software and created a specification that outlined the capablilities for the software.[1]

A contract was awarded to Computer Sciences Corporation (CSC) to develop the software. The name of the program is an acronym formed from NAsa STRuctural ANalysis. The NASTRAN system was released to NASA in 1968. In the late 1960s, The MacNeal-Schwendler Corporation (MSC) started to market and support its own version of NASTRAN, called MSC/NASTRAN (which eventually became MSC.Nastran).

The NASTRAN program has evolved over many versions. Each new version contains enhancements in analysis capability and numerical performance. In addition, many errors from previous versions are corrected. Today, NASTRAN is widely used throughout the world in the aerospace, automotive and maritime industries. It is considered the industry standard for analysis of aerospace structures.

In November 2002 MSC.Software reached a final agreement with the FTC to resolve an antitrust case against the company in connection with two acquisitions of rival CAE vendors. The FTC had alleged the acquisitions represented anticompetitive activities.

[edit] Software Architecture

NASTRAN is written primarily in FORTRAN and contains over one million lines of code. NASTRAN is compatible with a large variety of computers and operating systems ranging from small workstations to the largest supercomputers.

NASTRAN was designed from the beginning to consist of several modules. A module is a collection of FORTRAN subroutines designed to perform a specific taskā€”processing model geometry, assembling matrices, applying constraints, solving matrix problems, calculating output quantities, conversing with the database, printing the solution, and so on. The modules are controlled by an internal language called the Direct Matrix Abstraction Program (DMAP).

Each type of analysis available is called a solution sequence.

Some of the most common solution sequence codes are:

  • 101 - Linear Static
  • 103 - Modal
  • 105 - Buckling
  • 106 - Non-Linear Static
  • 107 - Direct Complex Eigenvalue
  • 108 - Direct Frequency Response
  • 109 - Direct Transient Response
  • 110 - Modal Complex Eigenvalue
  • 111 - Modal Frequency Response
  • 112 - Modal Transient Response
  • 129 - Nonlinear Transient
  • 153 - Non-Linear static coupled with heat transfer
  • 159 - Nonlinear Transient coupled with Heat transfer
  • 187 - DDAM (MSC.Nastran)
  • 200 - Design Optimization and Sensitivity analysis
  • 400 - Non-Linear Static and Dynamic (implicit) (MSC.NASTRAN native, superseeds 106, 129, 153 and 159)
  • 600 - Non-Linear Static and Dynamic (implicit) (front end to MSC.Marc)
  • 601 - Implicit Non-Linear (Adina)
  • 700 - Explicit Non-Linear (LS Dyna)
  • 701 - Explicit Non-Linear (Adina)

[edit] Associated Software

NASTRAN is primarily a solver for finite element analysis. It does not have functionality that allows for graphically building a model or meshing. All input and output to the program is in the form of text files. However, multiple software vendors market pre- and post-processors designed to simplify building a finite element model and analyzing the results. These software tools include functionality to import and simplify CAD geometry, mesh with finite elements, and apply loads and restraints. The tools allow the user to submit an analysis to NASTRAN, and import the results and show them graphically. In addition to pre- and post-processing capabilties, several Nastran vendors have integrated more advanced nonlinear capabilities into their Nastran products.

[edit] Flavors of NASTRAN

Currently there are numerous commercially available FEA products that are based on the NASTRAN source code, or read a Nastran input file but provide independent solver technology; these include:

  • MSC.Nastran and MD.Nastran
  • NEi Nastran
  • NX/NASTRAN
  • NASTRAN-xMG

[edit] MSC.Nastran

MSC Nastran is the original commercial Nastran product started by Dr. Richard MacNeal. For many years, MSC maintained a monopoly on the NASTRAN source code, which ended in June 2003 by the purchase by EDS of MSC.Nastran v2001 source code.

[edit] NEi Nastran

NEi Nastran is a powerful, general purpose finite element analysis solver used to analyze linear and nonlinear stress, dynamics, and heat transfer characteristics of structures and mechanical components. NEi Nastran represents the latest in FEA technology with one of the fastest iterative solvers on the market along with accurate solutions that have been trusted for over 15 years by companies in all industries. It is available on a wide variety of platforms including 32-bit and 64-bit Windows, Linux, and Unix operating systems.

[edit] NX/Nastran

NX Nastran resulted from the 2003 purchase of a royalty-free license for the software product MSC.Nastran by EDS, to the benefit of its UGS PLM Solutions division (now spun-off from EDS and called UGS). NX Nastran is based on the MSC.Nastran 2001 source code and is fully compatible with MSC.Nastran. The principal advantages of NX Nastran are lower price and a faster software development cycle.

The purchase included a perpetual, worldwide, royalty-free, nonexclusive license of the software program MSC.Nastran, other assets related to the software, and all intellectual property rights acquired as a result of MSC's acquisitions of Universal Analytics Inc. and Computerized Structural Analysis & Research Corp. in 1999).

[edit] NASTRAN-xMG

Built from the same base code as the original NASTRANĀ® software created by NASA that includes the original NASTRAN architecture and DMAP language, NASTRAN-xMG provides unlimited problem size, high-speed solver technology, and substructuring analysis options. The principal founder of the company is Dr. Richard H. MacNeal.

[edit] See also

[edit] Notes

  1. ^ MacNeal, Richard H., page i., "The NASTRAN Theoretical Manual", December 1972

[edit] External links

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