MSC Software "Model of the Month" Part 2

If you have arrived here from the MSC/NASTRAN Model of the Month page, welcome to the Collier Research Corporation website.  This page continues to describe the benefits of HyperSizer to a NASA-designed aerospace plane.  Please read on...

How is HyperSizer used to Analyze and Optimize the Aerospace Plane?

Define Structural Components

While in the FEM building process, modelers assign the same property data to groups of elements. These groupings of elements share the same PSHELL or PBAR record. HyperSizer uses these groupings as structural components for two primary purposes.

The first purpose is to identify the smallest, practical manufacturable piece of hardware that can be sized independently. The second purpose is to be able to efficiently analyze structure with widely varying load distributions. Statistical methods are used to resolve peak loadings across structural components, and, by so doing, solve the difficult 'pulling-loads' problem that occurs for any automatic analysis procedure. In this way, analyses and optimizations are performed for the structural components, not for the finite elements of the model. The figure illustrates the identified structural components of the aerospace vehicle.

Identify materials, panel and beam concepts, dimension ranges and analysis methods

With an infinite number of possible combinations, HyperSizer was able to make the optimization and analysis manageable by:

Filtering materials
HyperSizer's integrated database search engine containing metallic, composite, honeycomb and foam materials is used to filter a reduced set of materials...

Selecting Design Concepts
Over 40 unique panel and beam concepts are include such as hat and Z stiffened panels, honeycomb sandwiches and I section beams

Optimizing composite layups
An included library of over 1800 industry preferred layups makes layup optimization a snap.

Select Analysis methods
HyperSizer includes over 100 potential failure modes that are interactively enabled or disabled for ultimate and limit loads.

Setup Load Conditions

HyperSizer couples tightly with MSC/NASTRAN to obtain 'design-to' running loads for the aerospace plane. The contours here show the running loads for the vehicle under Mach 6 aerodynamic loading.
	Very accurate equivalent plate generalized stiffness terms are generated for the composite stiffened panels using exact cross sectional dimensions. Composite layups, temperature dependent properties, thermal gradients and the complex unsymmetric nature of panels leading to membrane-membrane coupling are accurately represented. Tight coupling with MSC/NASTRAN allows finite element properties and materials (PSHELL, PBAR, MAT2, MAT1) to be automatically generated and included in the FEA to obtain correct and consistent running loads.

The vehicle was analyzed and optimized to three distinct thermal environments: Mach 6 flight, Mach 3 flight, and takeoff/landing. In addition, six loading conditions were considered including aerodynamic pressure, thermal, landing and runway bump loads.

Analyze and Optimize - Designs on the Fly

Optimization starts with accurate and comprehensive analysis

The structure is analyzed using literally hundreds of strength and stability methods ranging from closed form, traditional hand calculations repeated every day in industry to more advanced panel buckling algorithms.  Some of these methods are modern instability algorithms such as those used for unsymmetric panel buckling.  Others are more traditional, simplistic hand calculations as shown here with the honeycomb analysis.

Margin-of-safety reporting for every potential failure provides the engineer with a powerful insight into the structural problem.

Design concurrently with multiple engineers

HyperSizer includes a fully relational database management system which allows multiple users to work on the vehicle design concurrently across a local area network. In addition, multiple projects are stored in the same HyperSizer database which meaning that archiving of the aerospace plane project and data are automatic. If temporarily pulled off of the aerospace plane project, you can come back weeks later and pick up right where you left off.