COMPOSITE ANALYSIS AND
STRUCTURAL SIZING SOFTWARE
 

Version History Detail

Version History Release Date
Click links to read more:
5.2.17 2008 March
5.0.0 2008 January
4.12.3 2007 May
4.12.1 2007 April
4.11.0 2007 February
4.10.4 2007 January
4.10.3 2006 December
4.10.2 2006 November
4.9.0 2006 October

4.8.6

2006 September

4.7.0

2006 July
4.6.2 2006 March
4.5.0 2005 September
Older Versions Prior to 2005 September

   

Version 5.2.17 Released 2008 March

New Capabilities

  • Stress Reports are automatically generated in Word, to include figures, equations, sample calculations, summary margin-of-safety tables, and table of contents.

  • Major rewrite has been completed, including reorganization of information. 
      
  • Stress report generation speed has been increased.

  • Visual progress indicators have been added.  This prevents the software from “locking up” while generating large stress reports.

  • Sample calculations have been added for all analysis methods.  In this capability, the equations for each method are shown and then sample values used in the analysis of your project are included:
Sample Calculations
  • For more information and to see a sample stress report, go to: http://www.stressreports.com

  • Centrally set database default values for all analysis methods.  This allows the user to set defaults for all failure method independent of any particular project.  In the example shown here, the user has turned composite material strength Hoffman interaction on, and turned all other composite failure analyses off.

Database Defaults

  • Apply values for any component based data (e.g. load factors, buckling knockdowns, failure methods, etc.) from the current component to all components in the current group, all components in the current assembly, all components in the current project, or set the current setting as a database default which can be applied to other projects in the same database.

    Component based data load factors buckling

  • A backdoor flag option has been added to allow HyperSizer to automatically calculate a curved panel knockdown factor using the process described in NASA publication SP-8007.  The knockdown factor calculation can be turned on and off for a project through the backdoor file and will be included in analysis, optimization and the stress reports.  This capability will be included in the normal HyperSizer GUI starting in version 5.3.
Corrections or Improvements
  • Local Pressure Calculation for Uniaxial Stiffened Panels has been improved.

  • In previous versions, the local moment, shear and deflection between stiffeners due to pressure on the facesheet was not calculated properly for situations where the flange thickness was greater than the skin thickness.  This has been corrected and verified against detailed FEA in Version 5.2.16.

  • A problem was fixed where the HyperSizer GUI became very slow if very large component, element, or grid IDs (>9,000,000) were used in the imported FEM.  HyperSizer will now efficiently process FEMs with IDs up to 99,999,999.  The speed of the GUI will be the same whether large or small IDs are used.

  • The Sizing form is now a “Sizeable” window.  This removes the problem, especially on the Failure tab, where analysis method names were truncated and not viewable because the window size was too small.
  • Database Import improvements
    • Database default settings can be imported from one database to another. 
    • When importing from one database to another, analysis results can be imported as long as it is the same database version.  In previous HyperSizer Versions, whenever importing from one database to another, all analysis results would be lost requiring the analysis to be re-run by the user.
    • A correction was made to the import of some user-defined palettes.
  • Easier navigation of components/groups/assemblies from the HyperSizer graphics.  The user can now switch from one assembly view to the next by pressing a button on the graphics form.  In previous versions, to switch assemblies, the user was forced to go to the Sizing form.

  • Minimum margin of safety is now displayed at the top of the sizing form for every component.

  • Minimum margin of safety

  • Workspaces are now created from the database tree, rather than manually copied from a template.  To create a new workspace, simply click on the Workspace branch of the tree and select “Create Workspace.”
  • Permissions to the HyperSizer database were fixed  to allow the HyperSizer Admin account to save new database defaults.
  • A problem was fixed that caused an application error when pulling up the Graphics window for the first time for a newly created Workspace.
Version 5.0.0 Released 2008 January

Corrections or Improvements

     

    Test Data Driven Reliability Analysis (Stochastic Optimization)

    • The new reliability analysis provides more structural integrity (reliability) while also reducing structural weight
    • User’s can conveniently go back and forth between traditional deterministic analysis and the reliability analysis to assess margin-of-safety impact of new method
    • Based on test data provided in the installed HyperSizer database, and on user entered test data, correlation factors can be established for each unique analysis method
    • Two correlation factors are established, one for stochastic data scatter, and one for analysis inaccuracy
    • The two correlation factors, per analysis method, can be used for selecting the reliability percentage of a particular analysis/sizing
    • This new capability is published in a AIAA Structures, Structural Dynamics & Materials 2005 conference papers (available from the Downloads» page)
      • Consistent Structural Integrity in Preliminary Design", 46th AIAA/ASME/ASCE/AHS SDM Conference, Austin,TX April 2005
      • Abstract
        • Coupling analytical methods to experimental results forms the basis of consistent structural integrity by analysis. By establishing repeatable statistical variance from building block test data for unique failure modes, it is possible to identify correlation factors (CFs) that account not only for analysis inaccuracy, but also observed scatter in test results. Industry accepted failure analysis predictions then can be used to design more robustly and to avoid unanticipated design flaws discovered in final design, or worse yet lead to part failure. The CFs can be used to adjust the individual margins-of-safety to produce more consistent structural integrity in the design and dependability in weight predictions of an aerospace vehicle. Such a capability is most useful during preliminary design where 80% of the design decisions carry forward, including the uninformed ones that bring with them undesirable difficulties of meeting weight goals, passing structural testing on the first try, and costly certification. The presented approach has been implemented in the HyperSizer® automated design tool that results in significant design cycle time reduction with the ability to analyze orders of magnitude more design configurations. Substantial risk reduction in final design is achieved from the integration and use of correlated, higher fidelity tools earlier in the design process. Presented are summary results from a recent Long Range Strike Aircraft preliminary design that compares the traditional, zero-margin for all failure modes approach, vs. the presented approach that achieves the same % reliability for all potential failure modes. Included are identified areas of the vehicle sized the traditional zero-margin method that results in an unexpected and unacceptable low reliability even though it is 9% heavier then reliability based sizing.

    Hundreds of test data cases included with delivered database

    • Test data validates many HyperSizer failure analyses:
      • Composite material failure strength
      • Panel buckling
      • Honeycomb sandwich
      • Bonded joints
      • Users can now enter their own test data for structural certification
      • Histograms of the test data scatter are automatically graphed
      • Reliability Analysis based on test data correlation

    User Manual Updates

    • HyperSizer Basic Manual (Reference Sections)
    • HyperSizer Pro Manual (Detailed Sizing and Analysis Application)
    • Reliability and Test Data
    • Object Model Programming Manual

    Damage Tolerance Residual Strength Sizing

    • Calculation of Strain Energy Release Rates (SERR) for comparison to critical energy release rates GIc and GIIc (a rapid, non-FEA, Virtual Crack Closure Technique, VCCT, with verification test cases)
      •      for crack between laminate plies
      •      for crack between skin and flange of bonded stiffened panel

     

Version 4.12.3 Released 2007 May

Corrections or Improvements

  • Correction to orthogrid local pocket buckling to account for facesheet/stiffener interaction
    • The interaction of the stiffener with the facesheet of an orthogrid panel has the effect of partially fixing the edges of the facesheet pocket against rotation. This can lead to over-conservative predictions for facesheet local pocket buckling
  • Fix for import of NASTRAN CBARs
    • In some situations, orientation vectors could be incorrectly interpreted from the NASTRAN run-deck if the orientation vector components were entered in scientific format

 

Version 4.12.1 Released 2007 April

New Capabilities

  • Local Buckling Knockdown Factor included on Buckling Tab of the Sizing form
  • Breakout of individual correction factors for orthotropic lamina material properties. Separate correction factors can now be entered to account for composite ply environmental and manufacturing effects, including:
    • Barely Visible Damage (BViD)
    • Automatic Fiber Placement (AFP)
    • Aging
    • Lamina-Laminate Ply Angle Percentage Correction
    • Pre-cure, Co-Cure and Co-Bond Corrections
    • Laminate bending correction factor
  • New Failure Methods
    • Sandwich Core Shear Strength Longitudinal/Transverse Interaction

      Fsul = Core Longitudinal (ribbon) Shear Strength Allowable
      Fsuw = Core Transverse Shear Strength Allowable
      Ksscf = Core Shear Strength Correction Factor

    • NASA SP-8007 Cylindrical Panel Buckling Method
      • Ref: NASA SP-8007, “Buckling of Thin-Walled Circular Cylinders”, Section 4.3
      • For simply supported, full cylinders (e.g. fuselage or cylindrical tanks), this method compares very closely, but has the advantage over HyperSizer’s built-in numerical buckling solution of being very efficient and therefore greatly speeding up optimizations that are controlled by global panel buckling
  • HyperFEMGen Automated Local Mesh Generation
    • A new backdoor capability has been developed to automatically create local finite element models (NASTRAN Format) that have consistent applied boundary conditions and loadings to perform independent checks of HyperSizer analyses.
    • These local FEMs can be run directly in NASTRAN without modification.
    • Local FEMs can be used for:
      • Static Analysis
      • Local buckling
      • Global/panel buckling
      • Crippling/Non-linear post buckling
    • Features such as holes and cutouts (e.g. windows) can be included in the local mesh
    • Concepts currently supported are Bonded I-stiffened, bonded hat and two-sheet stiffened, orthogrid stiffened panels.
     

Corrections or Improvements

  • Reads the TEMP(INIT) card from a NASTRAN deck case control to get a non-room temperature reference temperature.  This allows HyperSizer to do elevated temperature analysis, where temperature dependent material properties are considered, without introducing thermal stress effects.

 

Version 4.11.0 Released 2007 February

New Capabilities

  • Provided a backdoor option, “Local Buckling Knockdown Factor” which provides a separate knockdown factor for local buckling failure modes. In previous versions, local buckling failure modes used the same knockdown factor as global buckling failure modes. This feature will be integrated into the Buckling tab of the sizing form in version 4.12.

Corrections or Improvements

  • Added import of area non-structural masses (NSM) from NASTRAN property cards (PCOMP, PSHELL, etc) into HyperSizer as “Added Weight” on the sizing form Options tab. These non-structural masses are tracked by HyperSizer and exported back to the finite element model for iteration. To import non-structural masses, the option “Import Non-Structural Masses from FEM…” must be selected BEFORE importing the finite element model.

  • Non-structural masses (or Added Weights) are now by default, not included in weights reported on the Sizing Form, in the Summary Tab, or in the HyperSizer Graphics weight reporting. This behavior can be overridden by setting the backdoor option, “Remove Added Weight for Reporting” to False.

  • When sizing a structure to a minimum stiffness (i.e. A11, A22, D11, D22, etc. ), corrected the failure criteria to always use the minimum of either tension or compression stiffnesses when calculating the margin of safety. In previous versions, would default to only using the compression based stiffness terms when reporting to the Computed Properties tab and calculating the margin.

 

Version 4.10.4 Released 2007 January

Corrections or Improvements

  • Automatically turns off simple BC panel buckling failure modes for panels that include non-simple boundary conditions. These failure modes, if turned on, will now return the code N/A into the Failure Tab Margin of Safety. These failure modes will not affect the sizing.

  • Correction to stress reports when using All Load Case Details (highest level of detail) when also reporting element based analysis results. A buffer overrun would cause an error and return no results.

  • Correction to database import code when importing from one 4.10 database to another. In previous versions, there was possibility of data loss for some of the more advanced material and project data during the import procedure.

  • Correction for “Maximum Principal Stress” metallic failure mode. In some situations, this failure mode would incorrectly return a margin of safety of “-1.0”.

  • Correction of controlling BUCKLING vs STRENGTH reporting in the “Free Body Diagram Output” section of the FBD tab of the Sizing Form. In previous versions, this would always report STRENGTH as the controlling failure method regardless of the actual failure method.

 

Version 4.10.3 Released 2006 December

Corrections or Improvements

  • Correction to import of finite element models with non-english standard units (e.g. mm, Pa, N, etc) that reference different coordinate systems. In Version 4.10.2, the nodes of a model that is specified to be non-english units will not be translated correctly on import.

 

Version 4.10.2 Released 2006 November

New Capabilities

  • Correctly calculates the reduced local pressure bending effects for the pocket of an orthogrid stiffened panel.
    • For stiffened concepts where stiffeners run in the circumferential direction, a large percentage of applied pressure is reacted in hoop force in the stiffeners, however a small portion will be reacted by the bending stiffness of the pockets between stiffeners. This bending stiffness effect is now correctly accounted for as a reduced pressure in the local pressure bending calculation.
  • Calculates through-thickness, ply-by-ply out-of-plane shear stresses for laminates and sandwiches from the globally applied transverse shear forces, Qx and Qy.
    • Introduces a new “Interlaminar Strength” failure interaction equation:
                                 
 

Corrections or Improvements

  • Automatically turns off flat panel buckling failure modes for curved panels. These failure modes, if turned on, will now return the code N/A into the Failure Tab Margin of Safety. These failure modes will not affect the sizing.
  • Automatically turns off Panel Level Superimpose Pressure moment and shear effects for curved panels. The assumption is that for curved panels, the pressure will be reacted principally by hoop tension and therefore inappropriate to calculate reaction edge and midspan bending moments and shears.
  • Reduces the threshold of (Radius / Span) for assuming a panel is “flat” when importing a finite element model. In previous versions, a panel was assumed to be flat if Radius/Span > 50. In Version 4.10.0, a panel is assumed flat for Radius / Span > 10. The user can override the software’s assumption of flat or curved by clicking the “Panel is Curved” checkbox on the Buckling Tab.

  • Updates the Honeycomb Core Shear Strength calculation to derive the core shear stress from the core thickness + ½ the facesheet thicknesses rather than the full panel height.
                        

  • Correction to laminate percentage ply based strain allowables where a laminate is hybrid (more than one ply material) or has uneven distribution of ply thicknesses. In previous versions, HyperSizer assumed that all plies have the same thickness when determining the percentage of plies in each direction.

  • Corrected percentage ply based analysis to assume that woven (fabric) plies contain 50% 0° plies and 50% 90° plies. In previous versions, woven plies were treated the same as tape plies and did not take their biaxial strength into account.

 

Version 4.9.0 Released 2006 October

New Capabilities

  • Interactively create and re-define components, groups, and assemblies on the FEM using HyperSizer native graphics.
    • Create components and move individual elements from one component to another by simply clicking individual elements in the graphics.
    • This substantial new capability greatly increases the productivity of FEM and FEA post processing and modification and may free up PATRAN and FEMAP licenses for model building and preprocessing.
  • Two new isotropic failure criteria
    • “Maximum Shearing Strain”
    • "Maximum Principal Stress”
 

Corrections or Improvements

  • Renamed grid stiffened panel concepts to conform more closely to industry standard nomenclature.
 

Old Name

 

NEW

 

BiGrid

 

OrthoGrid

 

AngleGrid

 

WaffleGrid

 

OrthoGrid

 

AngleGrid

  • Improvement to thermoelastic formulation of Orthogrid panels.  Correctly accounts for the D33 bending-twisting stiffness of 0 and 90 webs.
  • Corrected sign convention graphic for grid-stiffened panels on the Concepts tab.  In the previous version, the z axis was pointing in wrong direction.

 

Version 4.8.6 Released 2006 September

New Capabilities

  • HyperFEA™: Automated iteration between HyperSizer and a finite element solver.
    • This is a fundamental new capability that also includes global FEA response in the sizing optimization process.
    • See brochure at HyperFEA™»
  • Re-Designed Project Setup Form:
    • Setup tab re-organized to a more intuitive format
    • Limit and Ultimate load factors can now be applied to individual load sets. Previously, load factors were only assigned on a component-by-component basis and were assumed to be the same for all load sets
    • Multiple load sets can be selected and modified at one time. Previously the user was required to modify one load set at a time
    • Load Cases created automatically on import rather than requiring the user to create load cases individually
    • Multiple load cases can now be selected, activated, deactivated, or deleted as one unit rather than requiring individual manipulation
  • Weight/Mass import and export from the FEM
    • Import of non-structural masses from the FEA as “Added Weight”
    • HyperSizer will read the WTMASS parameter from the FEM and use it when exporting densities and non-structural masses to the updated FEM
    • A user choice is supplied for exporting masses in MASS units or WEIGHT Units
  • User selected reference plane choice for unstiffened laminates and sandwich panels rather than the HyperSizer default reference plane of the midplane of the upper facesheet. This enhancement applies only to panels in the Unstiffened/Sandwich Panel Family.
  • Improved speed and formatting of Microsoft Word based stress reports

 

Version 4.7 Released 2006 July

New Capabilities

New Margin-of-Safety Stress Report

  • A new stress report is generated in Word document format.
    • This is a fundamental new capability.
    • The HTML format will still be available.
  • The Word document includes margins-of-safety for all possible combinations of conditions.
  • Table of contents, section headers, and graphics are generated automatically.

Element based analysis/sizing

  • Analysis and margin-of-safety (MS) reporting on an element-by-element basis for each component
  • A table is created in the Word based stress report summarizing the minimum margin of each element of the model, sorted by increasing MS
  • Element based margins-of-safety are displayed in the HyperSizer graphics

Support of NASTRAN PCOMP layup definitions for composite materials

  • Import of PCOMP FEM data and automatic generation of HyperSizer layups, hybrid laminates, and sandwich panels
  • Automatic creation of HyperSizer groups based on PCOMP definitions
  • Export of HyperSizer layups into PCOMP FEM data
    • As alternative to A,B,D stiffness data defined as MAT2
  • Support of NASTRAN PCOMP reduces the time and effort required for initial HyperSizer project setup.

Additional failure criteria:

  • Strain based Tsai-Wu with ply based or laminate based strain allowables
    • This is in addition to the existing stress based Tsai-Wu
  • Directional X and Y core shear strength failure criteria (previous versions returned only the minimum of these two margins of safety)

Support of NASTRAN CBEAM

  • Support for the NASTRAN CBEAM element type

Specialized NEi/NASTRAN support

  • Highly efficient native binary file I/O for large models and hundreds of load cases

 

Corrections or Improvements

  • Cascading coordinate systems (i.e. coordinate systems that reference other coordinate systems) are now properly translated on HyperSizer import of a FEM
  • Unlimited include file nesting in a finite element model is now handled correctly
  • HyperSizer database template location is now user-configurable. This allows an organization to locate a template database (for example, with company maintained materials) in a common location from which all users' new databases will be created.

 

Version 4.6.2 Released 2006 March

New Capabilities

  • Closed cross section beams: Rectangular, circular, and elliptical tubes shapes for metallic and composite materials
  • Laminate based strain allowables: In addition to the AML (Angle Minus Load) approach, another approach is offered based on A, B, C, D, E polynomial empirical curve fit for strain allowable:

    Strain Allowable = A(%0)^2 + B(%0) + C(%45) + D + E(%45/0) + F(%0/45) + G(%45)^2

Corrections or Improvements

  • Johnson-Euler interaction: Correction for case where buckling and crippling loads are different values
  • Material only database: Fix for export of database
  • Object model programming: Completely updated and operational

 

Version 4.5 Released 2005 September

New Capabilities

  • HyperFinder™» automated methods and equations search tool: Searches thousands of pages of technical documentation on specific HyperSizer analytical methods including equations.
     
  • Damage tolerance sizing such as open hole tension (OHT), and after impact compression (OHC) both implemented on the ply and on the laminate level. The ply allowables are temperature dependent, and the laminate allowables are both temperature and layup sequence dependent. The user can enter their layup dependent allowables via a table entry format and HyperSizer will generate the plot interactively for verification to the user.
     
  • Laminate allowables can be entered as a function of either: % of 0 degree plies, % of 45 degree plies, or % of AML (Angle minus load/longitudinal) plies. With the laminate allowables, the four primary directions 0, 90, 45, and -45 are checked, using a bending moment correction factor of which the standard default value =1.3 can be user changed.
     
  • New graphic capabilities such as storing preferred view angles and display format. Standard and advance menus for plotting results. More data types are now available to plot on the FEM.
     
  • More descriptive margin-of-safety (MS) reporting on the GUI, such as reporting which failure analyses are missing data, which analyses are out of bounds, which analysis are NA to given loads or optimization choices, etc. The failure tab now displays along with numbers for MS, these alpha string codes.
     
  • Freeze an optimization. This permits the software to perform analyses with different criteria, such as adding a loadcase without changing the previous optimized design, HyperSizer reports the MS for these changes without resizing and without requiring the user to manually freeze out each sizing variable’s permutation. This minor capability has turned out to be quite useful.
     
  • Data entry checks on the material forms have been added, such as:

 

Corrections or Improvements

  • More accurate crippling analysis that includes the effects of bending moments and biaxial loadings. (Includes technical documentation)
  • More accurate and general pressure bending analysis for panels including beam-column amplification for solving offline from FEA the effects, for instance, of fuel.  (Includes technical documentation) 
  • Slight corrections to local buckling for long aspect ratio plates such as web stiffeners
  • Tension/compression controlling loads passed consistently (along with appropriate tension/compression dependent material properties) to the composite analysis form for interactive ply-by-ply plotting and MS reporting with the failure tab