Isogeometric shape optimization of missing rib auxetics with prescribed negative Poisson’s ratio over large strains using genetic algorithm

2021 ◽  
Vol 193 ◽  
pp. 106169
Author(s):  
Deepak Kumar ◽  
Leong Hien Poh ◽  
Ser Tong Quek
Keyword(s):  
Genetic Algorithm ◽  
Shape Optimization ◽  
Poisson’S Ratio ◽  
Poisson's Ratio ◽  
Large Strains ◽  
Negative Poisson’S Ratio ◽  
Negative Poisson's Ratio

Optimal design of a novel crash box with functional gradient negative Poisson’s ratio structure

2022 ◽  
pp. 095440702110686
Author(s):  
Guan Zhou ◽  
Pengfei Yan ◽  
Qi Wang ◽  
Shijuan Dai ◽  
Xiang Li ◽  
...  
Keyword(s):  
Genetic Algorithm ◽  
Poisson’S Ratio ◽  
Optimization Design ◽  
Inner Core ◽  
Poisson's Ratio ◽  
Negative Poisson’S Ratio ◽  
Functional Gradient ◽  
Vibration Resistance ◽  
Negative Poisson's Ratio ◽  
Nbi Method

Crashworthiness and anti-vibration performance play critical roles in the performance of passenger cars. Aiming at enhancing the crash resistance and vibration resistance of vehicles thus providing good protection for passengers and drivers, a novel crash box with three-dimensional double arrow type negative Poisson’s ratio structure with functional gradient filling inner core (FGNPR crash box) is introduced in this paper and its performance is studied in detail through the comparison with the conventional crash box and the crash box filled with the uniform gradient negative Poisson’s ratio structure (NPR crash box) in crashworthiness and vibration resistance. Furthermore, range analysis is used to screen out the design variables that have little influence on the evaluation indexes and eliminate them. Based on these, neighborhood cultivation genetic algorithm (NCGA) and non-dominated sorting genetic algorithm-ii (NSGA-II) are selected as the optimization algorithms to carry out optimization design respectively and a comparison is made between the two suboptimal results screened out based on the normal boundary intersection (NBI) method to determine the overall optimal solution. Results show that the optimized FGNPR crash box has better crashworthiness and vibration resistance over the other crash boxes and its performance is further verified based on the peak acceleration of B-pillar in full vehicle crash condition. This paper provides some theoretical reference support for the development and exploration of automobile crash box systems.

Multi-objective crashworthiness optimization of vehicle body with negative Poisson’s ratio structure based on factorial analysis

2020 ◽  
Vol 234 (14) ◽  
pp. 3329-3346
Author(s):  
Songchun Zou ◽  
Shijuan Dai ◽  
Wanzhong Zhao ◽  
Chunyan Wang ◽  
Han Zhang
Keyword(s):  
Genetic Algorithm ◽  
Poisson’S Ratio ◽  
Factorial Analysis ◽  
Poisson's Ratio ◽  
Vehicle Body ◽  
Surface Model ◽  
Structure Parameters ◽  
Negative Poisson’S Ratio ◽  
Multi Objective ◽  
Negative Poisson's Ratio

To improve vehicle side crashworthiness, this paper first introduces the negative Poisson’s ratio structure to the traditional B-pillar and proposes a negative Poisson’s ratio B-pillar. Then, the performance of the negative Poisson’s ratio B-pillar is studied in detail by comparison with a traditional B-pillar and honeycomb B-pillar. Aiming at the problem that the side crashworthiness is also significantly affected by the side structure parameters of vehicle body, the factorial analysis theory is adopted to screen out the side structure parameters with significant effect. Based on this, by combining the optimal Latin hypercube design and response surface model, a multi-objective optimization design is conducted for those structure parameters based on non-dominated sorting genetic algorithm II. Finally, the normal boundary intersection method is adopted to seek the Pareto optimal solution, and the simulation results show that compared with the traditional B-pillar, the negative Poisson’s ratio B-pillar optimized by non-dominated sorting genetic algorithm II has better comprehensive crashworthiness. The results of this paper can provide some basis for the design and optimization of vehicle side crashworthiness.

Free vibration and sound insulation of functionally graded honeycomb sandwich plates

2021 ◽  
pp. 109963622110204
Author(s):  
Fenglian Li ◽  
Wenhao Yuan ◽  
Chuanzeng Zhang
Keyword(s):  
Free Vibration ◽  
Poisson’S Ratio ◽  
Functionally Graded ◽  
Poisson's Ratio ◽  
Dynamic Equations ◽  
Sound Insulation ◽  
Sandwich Plates ◽  
Negative Poisson’S Ratio ◽  
Honeycomb Sandwich ◽  
Negative Poisson's Ratio

Based on the hyperbolic tangent shear deformation theory, free vibration and sound insulation of two different types of functionally graded (FG) honeycomb sandwich plates with negative Poisson’s ratio are studied in this paper. Using Hamilton’s principle, the vibration and vibro-acoustic coupling dynamic equations for FG honeycomb sandwich plates with simply supported edges are established. By applying the Navier’s method and fluid–solid interface conditions, the derived governing dynamic equations are solved. The natural frequencies and the sound insulation of FG honeycomb sandwich plates obtained in this work are compared with the numerical results by the finite element simulation. It is proven that the theoretical models for the free vibration and the sound insulation are accurate and efficient. Moreover, FG sandwich plates with different honeycomb cores are investigated and compared. The corresponding results show that the FG honeycomb core with negative Poisson’s ratio can yield much lower frequencies. Then, the influences of various geometrical and material parameters on the vibration and sound insulation performance are systematically analyzed.

Sign in / Sign up

Export Citation Format

Share Document