Bence Balogh - Academia.edu (original) (raw)
Papers by Bence Balogh
The 6th International Conference on Engineering Optimization EngOpt2018, 2018
The goal of the study is to develop numerical algorithms for the optimization of plated structure... more The goal of the study is to develop numerical algorithms for the optimization of plated structures. The formulation of the optimization problem is based on the global or local weak form of a 2D continuum, giving rise to the usage of either the finite element method or another. The results are illustrated by the application of FEM and the element free Galerkin (EFG) method. In the latter, the moving least squares (MLS) method is used to construct shape functions with compactly supported weight functions, to achieve meshless approximations of system state equations. The direct method is included to enforce the essential boundary conditions because of the lack of the Kronecker delta function property of MLS meshless shape functions. Methods are compared in terms of computational time, numerical issues, advantages and shortcomings, and overall applicability in general. From optimization point of view, the goal is to minimize the volume, while ensuring a certain level of stiffness and stresses. The solution is obtained by using both the homogenization method and mathematical programming. The study is enclosed by illustrative examples of isotropic plates with linear and nonlinear material behaviour
The plated structures are one of the most frequently used en-gineering structures. The object of ... more The plated structures are one of the most frequently used en-gineering structures. The object of this research work is the optimal design of curved folded plates. This work is an ongo-ing investigation. There are various solution methods to analyze this type of structures. Here the finite strip method is used. At first single load condition is considered, but later the multiple load conditions are used for the design. The base formulation is a minimum volume design with displacement constraint what is represented by the compliance. For the multiple loading two equivalent topology optimization algorithms can be elaborated: minimization of the maximum strain energy with respect to a given volume or minimization of the volume of the structure sub-jected to displacement constraints. The numerical procedures are based on iterative formulas which is formed by the use of the first order optimality condition of the Lagrangian-functions. The application is illustrated by numerical examples. ...
Mechanics Based Design of Structures and Machines, 2017
A numerical investigation is performed addressing the optimal design of stiff structures accounti... more A numerical investigation is performed addressing the optimal design of stiff structures accounting for uncertainty in loading amplitudes. A minimum volume problem is endowed with a stochastic compliance constraint handling normal distributions and solved adopting mathematical programming. The formulation, originally conceived for a single load case, is extended to handle multiple load cases. Numerical simulations are performed to test the proposed algorithms, pointing out features of the numerical procedures and peculiarities of the stochastic-based optimal solutions achieved for different values of the second order moments. Comparisons with respect to conventional deterministic layouts are provided, as well.
Transactions of the VŠB – Technical University of Ostrava, Civil Engineering Series., 2015
The aim of this study is to compare two available numerical tools for solving of partial differen... more The aim of this study is to compare two available numerical tools for solving of partial differential equations for the optimal design of structures. In the past years numerous methods were developed for topology optimization, from these we have adopted the optimality criteria (OC) approach. The main idea is that we state the optimal conditions, that the minimizer has to fulfil at the end of an iterative proves. This method however is not a general one, only advantageous in the case of separable problems, but comes with fast speed, easy programming, and a relative insensitivity of computational time to the number of variables. In the paper we suggest a new method for the elimination of a numerical error, the so called ‘checkerboard pattern’. In the presented examples we applied one loading case and an elastic material behaviour. The cost function is the net weight of the structure and upper bound of the compliance is set as the optimality constraint.
Periodica Polytechnica Civil Engineering, 2014
The plated structures are one of the most frequently used engineering structures. The object of t... more The plated structures are one of the most frequently used engineering structures. The object of this research work is the optimal design of curved folded plates. This work is an ongoing investigation. There are various solution methods to analyze this type of structures. Here the finite strip method is used. At first single load condition is considered, but later the multiple load conditions are used for the design. The base formulation is a minimum volume design with displacement constraint what is represented by the compliance. For the multiple loading two equivalent topology optimization algorithms can be elaborated: minimization of the maximum strain energy with respect to a given volume or minimization of the volume of the structure subjected to displacement constraints. The numerical procedures are based on iterative formulas which is formed by the use of the first order optimality condition of the Lagrangian-functions. The application is illustrated by numerical examples. Keywords optimization • multiple loading • curved plate • curved folded plate • optimal layout • optimality criteria method • optimal design
The 6th International Conference on Engineering Optimization EngOpt2018, 2018
The goal of the study is to develop numerical algorithms for the optimization of plated structure... more The goal of the study is to develop numerical algorithms for the optimization of plated structures. The formulation of the optimization problem is based on the global or local weak form of a 2D continuum, giving rise to the usage of either the finite element method or another. The results are illustrated by the application of FEM and the element free Galerkin (EFG) method. In the latter, the moving least squares (MLS) method is used to construct shape functions with compactly supported weight functions, to achieve meshless approximations of system state equations. The direct method is included to enforce the essential boundary conditions because of the lack of the Kronecker delta function property of MLS meshless shape functions. Methods are compared in terms of computational time, numerical issues, advantages and shortcomings, and overall applicability in general. From optimization point of view, the goal is to minimize the volume, while ensuring a certain level of stiffness and stresses. The solution is obtained by using both the homogenization method and mathematical programming. The study is enclosed by illustrative examples of isotropic plates with linear and nonlinear material behaviour
The plated structures are one of the most frequently used en-gineering structures. The object of ... more The plated structures are one of the most frequently used en-gineering structures. The object of this research work is the optimal design of curved folded plates. This work is an ongo-ing investigation. There are various solution methods to analyze this type of structures. Here the finite strip method is used. At first single load condition is considered, but later the multiple load conditions are used for the design. The base formulation is a minimum volume design with displacement constraint what is represented by the compliance. For the multiple loading two equivalent topology optimization algorithms can be elaborated: minimization of the maximum strain energy with respect to a given volume or minimization of the volume of the structure sub-jected to displacement constraints. The numerical procedures are based on iterative formulas which is formed by the use of the first order optimality condition of the Lagrangian-functions. The application is illustrated by numerical examples. ...
Mechanics Based Design of Structures and Machines, 2017
A numerical investigation is performed addressing the optimal design of stiff structures accounti... more A numerical investigation is performed addressing the optimal design of stiff structures accounting for uncertainty in loading amplitudes. A minimum volume problem is endowed with a stochastic compliance constraint handling normal distributions and solved adopting mathematical programming. The formulation, originally conceived for a single load case, is extended to handle multiple load cases. Numerical simulations are performed to test the proposed algorithms, pointing out features of the numerical procedures and peculiarities of the stochastic-based optimal solutions achieved for different values of the second order moments. Comparisons with respect to conventional deterministic layouts are provided, as well.
Transactions of the VŠB – Technical University of Ostrava, Civil Engineering Series., 2015
The aim of this study is to compare two available numerical tools for solving of partial differen... more The aim of this study is to compare two available numerical tools for solving of partial differential equations for the optimal design of structures. In the past years numerous methods were developed for topology optimization, from these we have adopted the optimality criteria (OC) approach. The main idea is that we state the optimal conditions, that the minimizer has to fulfil at the end of an iterative proves. This method however is not a general one, only advantageous in the case of separable problems, but comes with fast speed, easy programming, and a relative insensitivity of computational time to the number of variables. In the paper we suggest a new method for the elimination of a numerical error, the so called ‘checkerboard pattern’. In the presented examples we applied one loading case and an elastic material behaviour. The cost function is the net weight of the structure and upper bound of the compliance is set as the optimality constraint.
Periodica Polytechnica Civil Engineering, 2014
The plated structures are one of the most frequently used engineering structures. The object of t... more The plated structures are one of the most frequently used engineering structures. The object of this research work is the optimal design of curved folded plates. This work is an ongoing investigation. There are various solution methods to analyze this type of structures. Here the finite strip method is used. At first single load condition is considered, but later the multiple load conditions are used for the design. The base formulation is a minimum volume design with displacement constraint what is represented by the compliance. For the multiple loading two equivalent topology optimization algorithms can be elaborated: minimization of the maximum strain energy with respect to a given volume or minimization of the volume of the structure subjected to displacement constraints. The numerical procedures are based on iterative formulas which is formed by the use of the first order optimality condition of the Lagrangian-functions. The application is illustrated by numerical examples. Keywords optimization • multiple loading • curved plate • curved folded plate • optimal layout • optimality criteria method • optimal design