Aircraft Structural Safety

Design Optimization under Uncertainty

Design Optimization of Automobile Structures for Crashworthiness

Metamodel (Surrogate Model)-Based Design Optimization

Life Assessment of Jet Engine Components

Multidisciplinary Design Optimization

Multilevel Modeling/Multiscale Modeling/Microstructure-Property Modeling

----------------------------------------------------------------------

Aircraft Structural Safety

  • investigated effects of error, variability, testing and safety factors on aircraft safety, analyzed weight tradeoffs of coupon tests, structural element tests and certification tests for aerospace structures
  • explored the weight savings from cryogenic laminates (used in hydrogen tanks) by uncertainty reduction
  • analyzed effects of uncertainty reduction measures on the maximum allowable load of a sandwich structure
  • proposed reliability-based design optimization design methodology, which requires only minimal statistical information on stress distributions

 

Design Optimization under Uncertainty

  • developed a new method (guided tail modeling, GTM) for reliability assessment of highly safe mechanical systems
  • developed a new reliability estimation method (UDR+EGLD) based only on four statistical moments of the limit-state function and extended generalized lambda distribution
  • carried out multi-objective crashworthiness optimization of tapered thin-walled tubes with axisymmetric indentations
  • performed reliability-based design optimization of control arm of Corvette while making use of a multiscale material model in the structural analysis
  • quantified uncertainty in damage evolution in a metallic structure by using a multiscale material model
  • conducted uncertainty propagation analysis for compaction parameters of the Modified Drucker-Prager Cap model, used in assessing the powder metal performance of automotive components
  • performed experimental robust optimization of machining process of hardened stainless steel with alumina based ceramic tool
  • performed shape and sizing optimization of automotive structures (with deterministic and probabilistic design constraints)

 

Design Optimization of Automobile Structures for Crashworthiness

  • improved accuracy of vehicle crash response predictions by using ensemble of metamodels
  • performed system reliability based vehicle design for crashworthiness and explored the effects of various uncertainty reduction measures
  • involved in a comparative study of design optimisation methodologies for side-impact crashworthiness comparing injury-based and energy-based criteria
  • developed a multi-objective optimization framework for design of tapered thin-walled tubes with axisymmetric indentations
  • worked on multi-objective robust design of energy-absorbing components using coupled process–performance simulations
  • increased automobile crash response metamodel accuracy through adjusted cross validation error based on outlier analysis
  • developed an optimization framework for design of tapered thin-walled tubes with lateral circular cutouts

 

Life Assessment of Jet Engine Components

  • performed heat-transfer, stress and fracture mechanics analysis of the engine sections starting from high pressure turbine to low pressure turbine using a finite element analysis software, MARC
  • carried out the crack growth analysis using AFGROW
  • assessed thermo-mechanical fatigue life of impingement cover pins used in F110-GE-100 engine (of an F-16 aircraft)

 

Metamodel (Surrogate Model)-Based Design Optimization

  • developed a new metamodeling technique based on the use ensemble of metamodels with optimized weight factors
  • investigated various approaches for constructing an ensemble of metamodels using local measures
  • proposed a new methodology for optimizing the shape parameters of radial basis functions

 

Multidisciplinary Design Optimization of a T-Tail Boom (conducted at EMBRAER, Sao Jose dos Campos, Sao Paulo, Brasil)

  • performed MDO of a tail boom of a generic T-tail aircraft in the presence of competing objectives of aerodynamics and structures (NASTRAN)
  • used multi-fidelity s approach to attain a desirable accuracy along with a reduced computational expense
  • developed correction response surfaces to reduce computational cost

 

Multilevel Modeling/Multiscale Modeling/Microstructure-Property Modeling

  • investigated product design optimization with microstructure-property modeling and associated uncertainties
  • performed sensitivity and uncertainty analysis of microstructure-property relations for compacted powder metals
  • conducted concurrent design of product-material systems using multilevel optimization