Detail Stress Analysis

Detail Stress Analysis Services are tailored to each company’s project needs. Our engineers can work on-site at your facility or from our offices. Either scenario allows us to work in parallel with you, progressing your design to meet critical design goals. Our HyperSizer engineers have provided their knowledge and expertise on many technical teams at NASA and major aircraft and space launch companies, helping engineers and designers to achieve optimum designs. 

Core Competencies

HyperSizer engineers have comprehensive structural aerospace experience in performing structural analysis and design with an emphasis on composite materials. A summary of capabilities and experience include:

• Adept at using HyperSizer for preliminary and detail design sizing optimization of full airframe and space vehicles, as well as for comprehensive failure analysis and detail stress analysis. Expert level HyperSizer user from the perspective of complete understanding of its purpose, scope of problems solved, and advantages when coupled with FEA.
• Effective communicators, both verbal and written. HyperSizer engineers are accustomed to reporting directly to NASA, Air Force Research Lab, and major aerospace companies and are able to verify and describe the application of HyperSizer to the customer design.

FEA Coupling

• Exceptional understanding of overall load paths and having an intuitive feel for the efficient use of structural concepts and materials.
• Hands on experience with the iterative design cycle of sizing structure and then updating the FEM to get updated FEA computed internal loads and margins-of-safety.
• Experience with applying external loads such as aerodynamic pressures, flight inertia, and localized forces for control surface, landing, and taxi loads to the FEM, and the FEA resolution of external loads into internal load paths. Experience with mechanical loads and thermal environments including thermally induced stresses and temperature dependent material properties.
• Ability to perform finite element analysis (FEA) with NASTRAN (and ABAQUS) and know good models from bad models, and the proper use of coarse models and fine mesh models. Extensive experience with the NASTRAN data types PSHELL, MAT2, PCOMP, MAT8, PBAR, PBARL.

Sizing Optimization

• Hands on experience sizing structure for minimum weight, with ‘real world’ practical design experience sizing composite laminates, fabrication rules of thumb, including ply drop ratios and layup patterns on complicated surfaces, such as padups around cutouts and bolted joints.  

Failure Analyses

• Applying appropriate failure theories, preparing structural analysis reports, and identifying critical load conditions and margins-of-safety.
• Knowledge of composite material failure theories ranging from classical in-plane laminate stress analysis to more advanced out-of-plane interlaminar shear and peel stress analysis, progressive failure and crack growth VCCT methods. Experience with both ply based (max strain, Tsai-Wu) and laminate based (AML, polynomial) strength prediction approaches and associated material allowables.
• Understanding and experience with issues related to choice of proper composite material allowables: pristine typical vs. damage tolerancedesign-to values; such as CAI, OHC, OHT, FHC, FHT, bearing by-pass, etc.
• Knowledge of stiffened panel different types of instability such as panel buckling, flexural-torsional buckling, local buckling, stiffener crippling, initial buckling and compression and shear IDT postbuckling collapse.
• Knowledge of sandwich panel unique failures such as facesheet wrinkling, dimpling, crimping, debonding of core from facesheet, core taper ramp downs, and flat wise tension.
• Experience with composite and metallic joints. Experience with analyzing adhesively bonded joints and bolted composite joints. Bolt patterns, design rules, fastener selection, etc.
• Experience with identifying and solving delamination and debond failures .
• Experience with the test data validation, building block process, and correlation to analysis methods
• Knowledge of requirements for final stress report writing and necessary documentation for supporting FAA airworthiness certification