The Experts below are selected from a list of 144 Experts worldwide ranked by ideXlab platform

Kaan Inal - One of the best experts on this subject based on the ideXlab platform.

  • Effects of coupling anisotropic yield functions with the optimization process of extruded aluminum front rail geometries in crashworthiness
    International Journal of Solids and Structures, 2017
    Co-Authors: Christopher P. Kohar, Abhijit Brahme, Jean Imbert, Raja K Mishra, Kaan Inal
    Abstract:

    Abstract Using advanced constitutive models in simulation tools can improve predictive capabilities of automotive structures in crashworthiness applications. This work presents the influences of coupling anisotropic yield functions into the size optimization of extruded front rails to maximize energy absorption characteristics. Finite element simulations of the extrusion crush response are performed using the von Mises (1913), Hosford (1972) and Barlat et al. (2005) Yld2004-18p yield functions. Each yield function is implemented into a 2-dimensional plane stress and 3-dimensional element formulation to highlight the modeling differences prior to optimization. The simulations are also compared to the experimental dynamic crush response of the extrusion. The response surface methodology (RSM) with the artificial neural network (ANN) metamodeling technique is coupled with the genetic algorithm (GA) optimization scheme to improve the specific energy absorption (SEA) through maximizing energy absorption and Minimizing Mass. A constrained and unconstrained Mass optimization study is performed to identify the sensitivity of global optimization to yield surface choice. Analytical models are derived to explain the influence of the yield surface on the convergence of optimization. The results highlight the importance of incorporating anisotropic yield functions into the optimization process.

  • development of high crush efficient extrudable aluminium front rails for vehicle lightweighting
    International Journal of Impact Engineering, 2016
    Co-Authors: Christopher P. Kohar, Amir Zhumagulov, Abhijit Brahme, Raja K Mishra, Michael J. Worswick, Kaan Inal
    Abstract:

    Abstract Understanding the behaviour of automotive structural components is essential for vehicle weight reduction and passenger safety. In this study, a novel framework is developed to design an optimized front rail that maximizes crash energy absorption characteristics. The new design is coupled with material and process development to provide a component with superior energy absorption and strength characteristics that is commercially sustainable. Simulations of the extrusion crush behaviour are performed using the anisotropic Barlat et al. (2003) Yld2000 yield functions. The simulations are compared to the dynamic crush results for this extrusion. The size of the structure is optimized using the response surface methodology, using artificial neural networks metamodels and simulated annealing optimization techniques. The specific energy absorption (SEA) is used as a single optimization objective function for maximizing energy absorption and Minimizing Mass. An analytical relationship that relates the SEA function to the crush efficiency is derived to show that a single optimization function parameter may be sufficient for Mass minimization. Analysis is performed to identify key extrusion operational parameters and the wall thickness is identified as the most important parameter to control during extrusion.

Christopher P. Kohar - One of the best experts on this subject based on the ideXlab platform.

  • Effects of coupling anisotropic yield functions with the optimization process of extruded aluminum front rail geometries in crashworthiness
    International Journal of Solids and Structures, 2017
    Co-Authors: Christopher P. Kohar, Abhijit Brahme, Jean Imbert, Raja K Mishra, Kaan Inal
    Abstract:

    Abstract Using advanced constitutive models in simulation tools can improve predictive capabilities of automotive structures in crashworthiness applications. This work presents the influences of coupling anisotropic yield functions into the size optimization of extruded front rails to maximize energy absorption characteristics. Finite element simulations of the extrusion crush response are performed using the von Mises (1913), Hosford (1972) and Barlat et al. (2005) Yld2004-18p yield functions. Each yield function is implemented into a 2-dimensional plane stress and 3-dimensional element formulation to highlight the modeling differences prior to optimization. The simulations are also compared to the experimental dynamic crush response of the extrusion. The response surface methodology (RSM) with the artificial neural network (ANN) metamodeling technique is coupled with the genetic algorithm (GA) optimization scheme to improve the specific energy absorption (SEA) through maximizing energy absorption and Minimizing Mass. A constrained and unconstrained Mass optimization study is performed to identify the sensitivity of global optimization to yield surface choice. Analytical models are derived to explain the influence of the yield surface on the convergence of optimization. The results highlight the importance of incorporating anisotropic yield functions into the optimization process.

  • development of high crush efficient extrudable aluminium front rails for vehicle lightweighting
    International Journal of Impact Engineering, 2016
    Co-Authors: Christopher P. Kohar, Amir Zhumagulov, Abhijit Brahme, Raja K Mishra, Michael J. Worswick, Kaan Inal
    Abstract:

    Abstract Understanding the behaviour of automotive structural components is essential for vehicle weight reduction and passenger safety. In this study, a novel framework is developed to design an optimized front rail that maximizes crash energy absorption characteristics. The new design is coupled with material and process development to provide a component with superior energy absorption and strength characteristics that is commercially sustainable. Simulations of the extrusion crush behaviour are performed using the anisotropic Barlat et al. (2003) Yld2000 yield functions. The simulations are compared to the dynamic crush results for this extrusion. The size of the structure is optimized using the response surface methodology, using artificial neural networks metamodels and simulated annealing optimization techniques. The specific energy absorption (SEA) is used as a single optimization objective function for maximizing energy absorption and Minimizing Mass. An analytical relationship that relates the SEA function to the crush efficiency is derived to show that a single optimization function parameter may be sufficient for Mass minimization. Analysis is performed to identify key extrusion operational parameters and the wall thickness is identified as the most important parameter to control during extrusion.

Jane H. Davidson - One of the best experts on this subject based on the ideXlab platform.

  • Mass transfer during sensible charging of a hybrid absorption/sensible storage tank☆
    Energy Procedia, 2012
    Co-Authors: Josh A. Quinnell, Jane H. Davidson
    Abstract:

    Abstract A concept for long term thermochemical storage based on absorption of aqueous CaCl2 is described and evaluated during sensible charging operation. The novelty of the desiccant storage tank is that strong and diluted salt solutions as well as water are stored in one vessel. An immersed heat exchanger and manifold provide the means to charge the tank without mixing solutions of different CaCl2 Mass fraction. The ability to heat the tank via natural convection, while Minimizing Mass transfer between regions of different salt Mass fraction, is elucidated via optical measurements of the velocity and CaCl2 Mass fraction distributions in a 1500 liter prototype tank. Over a wide range of the dimensionless parameters that govern mixing, the Mass transfer between layers of differing CaCl2 Mass fraction is low, typically with Sherwood numbers less than 100, and temperature stratification is maintained. Projected time scales for long term storage exceed 100 days.

Subhash Bhatia - One of the best experts on this subject based on the ideXlab platform.

  • Effect of Mass Transfer and Enzyme Loading on the Biodiesel Yield and Reaction Rate in the Enzymatic Transesterification of Crude Palm Oil
    Energy & Fuels, 2009
    Co-Authors: Subhash Bhatia
    Abstract:

    Efforts in Minimizing Mass transfer effects in enzymatic transesterification of crude palm oil in a biphasic system have always been the compromise between enzyme loading and agitation speed. Therefore, effect of enzyme loading and agitation speed on fatty acid methyl ester (FAME) productivity in terms of intrinsic and external Mass transfer limitations and the effective reaction time were determined using factorial design. FAME yield response was significantly affected by agitation speed, enzyme loading and reaction time, whereas initial reaction rate was solely dependent on the enzyme loading. Graphical plots of experimental results revealed that the Mass transfer effect for the transport of reactant from bulk liquid to immobilized lipase and within the intraparticle of immobilized lipase were absent at 150 rpm and 6.65% enzyme loading. Optimization conditions for a kinetically controlled domain proposed by the response surface methodology established 100% FAME yield in 4 h reaction time at initial reac...

Abhijit Brahme - One of the best experts on this subject based on the ideXlab platform.

  • Effects of coupling anisotropic yield functions with the optimization process of extruded aluminum front rail geometries in crashworthiness
    International Journal of Solids and Structures, 2017
    Co-Authors: Christopher P. Kohar, Abhijit Brahme, Jean Imbert, Raja K Mishra, Kaan Inal
    Abstract:

    Abstract Using advanced constitutive models in simulation tools can improve predictive capabilities of automotive structures in crashworthiness applications. This work presents the influences of coupling anisotropic yield functions into the size optimization of extruded front rails to maximize energy absorption characteristics. Finite element simulations of the extrusion crush response are performed using the von Mises (1913), Hosford (1972) and Barlat et al. (2005) Yld2004-18p yield functions. Each yield function is implemented into a 2-dimensional plane stress and 3-dimensional element formulation to highlight the modeling differences prior to optimization. The simulations are also compared to the experimental dynamic crush response of the extrusion. The response surface methodology (RSM) with the artificial neural network (ANN) metamodeling technique is coupled with the genetic algorithm (GA) optimization scheme to improve the specific energy absorption (SEA) through maximizing energy absorption and Minimizing Mass. A constrained and unconstrained Mass optimization study is performed to identify the sensitivity of global optimization to yield surface choice. Analytical models are derived to explain the influence of the yield surface on the convergence of optimization. The results highlight the importance of incorporating anisotropic yield functions into the optimization process.

  • development of high crush efficient extrudable aluminium front rails for vehicle lightweighting
    International Journal of Impact Engineering, 2016
    Co-Authors: Christopher P. Kohar, Amir Zhumagulov, Abhijit Brahme, Raja K Mishra, Michael J. Worswick, Kaan Inal
    Abstract:

    Abstract Understanding the behaviour of automotive structural components is essential for vehicle weight reduction and passenger safety. In this study, a novel framework is developed to design an optimized front rail that maximizes crash energy absorption characteristics. The new design is coupled with material and process development to provide a component with superior energy absorption and strength characteristics that is commercially sustainable. Simulations of the extrusion crush behaviour are performed using the anisotropic Barlat et al. (2003) Yld2000 yield functions. The simulations are compared to the dynamic crush results for this extrusion. The size of the structure is optimized using the response surface methodology, using artificial neural networks metamodels and simulated annealing optimization techniques. The specific energy absorption (SEA) is used as a single optimization objective function for maximizing energy absorption and Minimizing Mass. An analytical relationship that relates the SEA function to the crush efficiency is derived to show that a single optimization function parameter may be sufficient for Mass minimization. Analysis is performed to identify key extrusion operational parameters and the wall thickness is identified as the most important parameter to control during extrusion.