Home
Verification Problems
This manual presents solved verification models including NAFEMS problems.
Aerospace Verification
This manual presents solved aerospace verification models including NAFEMS problems.
Elements
OS-V: 0700 Twisted Cantilever Beam (Implicit Results)
MacNeal-Harder Test This is a twisted cantilever beam solved with solid and shell elements. A model is made with each element's type to investigate the effect of distorted elements with a high aspect ratio.

Welcome
What's New
View new features for OptiStruct 2025.
Overview
OptiStruct is a proven, modern structural solver with comprehensive, accurate and scalable solutions for linear and nonlinear analyses across statics and dynamics, vibrations, acoustics, fatigue, heat transfer, and multiphysics disciplines.
Tutorials
Discover OptiStruct functionality with interactive tutorials.
User Guide
This manual provides detailed information regarding the features, functionality, and simulation methods available in OptiStruct.
Reference Guide
This manual provides a detailed list and usage information regarding input entries, output entries, and parameters available in OptiStruct.
Example Guide
The OptiStruct Example Guide is a collection of solved examples for various solution sequences and optimization types and provides you with examples of the real-world applications and capabilities of OptiStruct.
Verification Problems
This manual presents solved verification models including NAFEMS problems.
- Aerospace Verification
  This manual presents solved aerospace verification models including NAFEMS problems.
  - NAFEMS Linear Elastic
  - Elements
    - OS-V: 0700 Twisted Cantilever Beam (Implicit Results)
      MacNeal-Harder Test This is a twisted cantilever beam solved with solid and shell elements. A model is made with each element's type to investigate the effect of distorted elements with a high aspect ratio.
    - OS-V: 0710 Curved Cantilever Beam
      MacNeal-Harder Test This is a curved cantilever beam solved with solid and shell elements. A model is made with each element's type to investigate the effect of distorted elements with a high aspect ratio.
    - OS-V: 0720 Straight Cantilever Beam
      MacNeal-Harder Test This is a straight cantilever beam solved with solid and shell elements. Three models (rectangular, parallelogram, trapezoidal) are made with each element's type to investigate the effect of distorted elements with a high aspect ratio.
    - OS-V: 0730 Scordelis-Lo Roof
      MacNeal-Harder Test The Scordelis-Lo Roof is a classical benchmark problem for shell elements. Analytical and experimental investigations were initially performed by Scordelis and Lo.
    - OS-V: 0740 Curved Strip Hook
      Raasch ChallengeThe Raasch challenge is a curved strip hook problem with a tip in-plane shear load, posed in 1990 by Ingo Raasch of BMW in Germany. The problem poses a significant challenge to shell elements because of the inherent coupling between three modes of deformation: bending, extension, and twist. OptiStruct is benchmarked against the Raasch challenge to assure its shell elements performance on Linear Static Analysis.
    - OS-V: 0750 Radial Stretching of a Cylinder
      Illustrates the use of asymmetrical elements (CTAXI) under uniform radial displacement in OptiStruct.
    - OS-V: 0760 MacNeal-Harder Solid Patch Test
      MacNeal-Harder TestThe patch test is a classical benchmark problem for the element. If it produces correct results for the test, the result for any problem solved with the element will converge toward the correct solution. The intended purpose of the proposed problem set is to ascertain the accuracy of finite element in various applications.
  - Aeroelastic Analysis
- NAFEMS Linear Elastic
- NAFEMS Thermo-elastic
- NAFEMS Heat Transfer
- NAFEMS Nonlinear Static Analysis
- NAFEMS Dynamic Response Analysis
- NAFEMS Random Response Analysis
- NAFEMS Normal Modes Analysis
- NAFEMS Composites
- Response Spectrum Analysis
- Elements
- Materials
- Fatigue Analysis
- Rotor Dynamics
- Frequency Response Analysis
- Explicit Dynamic Analysis
- Aeroelastic Analysis
Frequently Asked Questions
This section provides quick responses to typical and frequently asked questions regarding OptiStruct.

View All Altair HyperWorks Help

OS-V: 0700 Twisted Cantilever Beam (Implicit Results)

MacNeal-Harder Test This is a twisted cantilever beam solved with solid and shell elements. A model is made with each element's type to investigate the effect of distorted elements with a high aspect ratio.

veri_twist — Figure 1. FE Model of the Beam with Boundary Conditions and Loadcases

Model Files

Before you begin, copy the file(s) used in this problem to your working directory.

Benchmark Model

Six types of elements are used for this problem. They are tria-shell, quad-shell, and hexa-solid elements, each with 1st and 2nd order. Two loading cases, in-plane bending and transverse bending, are used for each model. For both load cases, unit loads are applied in a consistent fashion over all of the nodes at the tip of the beam.

Theoretical solutions for the deflections at the tip, computed by beam theory, are:


Load Type	Component	Value
In-plane bending	UY	0.001754
Transverse bending	UZ	0.005424

Linear Static Analysis Results

All results are normalized with the target value.


	In-plane Bending	Transverse Bending
QUAD4	0.988	0.992
QUAD8	1.014	1.062
TRI3	0.839	0.984
TRI6	1.161	1.215
HEX8	0.986	1.005
HEX20	1.017	1.052

Reference

MacNeal, R.H., and Harder, R.L., A Proposed Standard Set of Problems to Test Finite Element Accuracy, Finite Elements in Analysis and Design, 1 (1985) 3-20.