N151-009 TITLE: Novel Isogeometric Analysis Based Automation of High-Fidelity Finite Element Analysis Model Creation from Computer Aided Design

TECHNOLOGY AREAS: Air Platform

ACQUISITION PROGRAM: PMA 274

OBJECTIVE: Create a novel tool that uses isogeometric analysis techniques to integrate computer aided design (CAD) and finite element modeling (FEM) to increase the efficiency and automation of the development of a high fidelity analysis model of structural assemblies for design and repair optimization.

DESCRIPTION: A clear gap exists between the CAD files generated by designers and the analysis suitable geometries used in finite element analysis (FEA) codes. The CAD to FEA and FEA to CAD transition process is inefficient, laborious, and can introduce inaccuracies through the simplification of design features. The ability to automatically create high fidelity analysis models of structural assemblies is not available. Currently, every design iteration requires analytical models to be revised. Furthermore, changing core geometry through repairs drives the need for an updated CAD model. Using one model as the basis for design and analysis significantly reduces the time consuming process of model revision cycles.

Isogeometric analysis methods incorporating non-uniform rational B-spline (NURBS) modeling have shown considerable promise in terms of utilizing a single geometric CAD model which can be employed directly as an analysis model. T-spline extensions of NURBS modeling have allowed for local refinement and coarsening of a given model. Furthermore, isogeometric analysis is clearly advantageous in terms of reduced computational time and increased solution accuracy per degree-of-freedom over standard low-order finite element analyses.

An isogeometric modeling tool is sought that will increase the automation in the process of creating a high fidelity analysis model from CAD files (e.g. Computer Aided Three-dimensional Interactive Application (CATIA) files) or laser scanned surface digitizations. The analysis model will primarily be used for repair analysis including metallic or composite structures. The process should also facilitate transfer and integration of data amongst both design and analysis regimes. The tool should be applicable to aircraft modeling, structural improvement/development and data integration efforts. Ultimately, this tool should facilitate the integration of design with all required supporting analysis to determine structural integrity (i.e. static strength, fatigue and damage tolerance).

PHASE I: Develop and conceptually demonstrate the proposed isogeometric analysis approach to integration of CAD and finite element modeling. Demonstrate feasibility of applying this approach for structural analysis applications on a realistic, complex part and outline approach for further development in Phase II.

PHASE II: Develop a prototype tool used to increase automation in the creation of high fidelity analysis models using isogeometric analysis. Demonstrate use of the prototype tool through creation of an analytical model of selected structural components and compare structural response under various Navy approved test conditions to existing data, which will be provided as Government Furnished Information.

PHASE III: Implement validated algorithms and processes into an analysis tool that can be used for structural analysis applications. Demonstrate capability to incorporate repairs and structural optimization. Refine the prototype analysis tool into a released version of software. Develop a plan to determine the effectiveness of the software in an operationally relevant environment. Support the Navy with certifying and qualifying the system for Navy use.

PRIVATE SECTOR COMMERCIAL POTENTIAL/DUAL-USE APPLICATIONS: Most designs, modifications and repairs go through several iterations of computer aided design and finite element analysis modeling. The isogeometric analysis technique can be applied on any of these to significantly reduce the time consuming and labor intensive process of model revision cycles with the advantage of increased solution accuracy per degree-of-freedom as compared to standard low-order finite element analyses.

REFERENCES:
1. Cottrell, J. A., Thomas J. R. H., & Bazilevs, Y. (2009). Isogeometric Analysis: Toward Integration of CAD and FEA. United Kingdom: John Wiley & Sons.

2. de Borst, R., Crisfield, M. A., Remmers, J. J. C., & Verhoosel, C. V. (2012). Non-linear Finite Element Analysis of Solids and Structures (2nd ed.). United Kingdom: John Wiley & Sons, 2012.

3. Takizawa, K. & Tezduyar, T. E. (2012). Flapping Wing Aerodynamics of an Actual Locust. Bulletin for the International Association of Computational Mechanics Expressions, 32(12), 2-5.

4. Dörfel, M. R., Jüttler, B., & Simeon, B. (2010). Adaptive isogeometric analysis by local h-refinement with T-splines. Computer Methods in Applied Mechanics and Engineering 199(5-8), 264-275. doi:10.1016/j.cma.2008.07.012

KEYWORDS: Computer Aided Design; Modeling; Finite Element; Isogeometric; Structural Analysis; Adaptive Meshing

** TOPIC AUTHOR (TPOC) **

DoD Notice:   Between December 12, 2014 and January 14, 2015 you may talk directly with the Topic Authors (TPOC) to ask technical questions about the topics. For reasons of competitive fairness, direct communication between proposers and topic authors is not allowed starting January 15, 2015 , when DoD begins accepting proposals for this solicitation.

However, proposers may still submit written questions about solicitation topics through the DoD's SBIR/STTR Interactive Topic Information System (SITIS), in which the questioner and respondent remain anonymous and all questions and answers are posted electronically for general viewing until the solicitation closes. All proposers are advised to monitor SITIS (15.1 Q&A) during the solicitation period for questions and answers, and other significant information, relevant to the SBIR 15.1 topic under which they are proposing.

If you have general questions about DoD SBIR program, please contact the DoD SBIR Help Desk at (866) 724-7457 or webmail link.