FEMLIB: An Object-Oriented Framework for Optimization and Simulation

1995 ◽  
Author(s):  
Michael M. Tiller ◽  
Jonathan A. Dantzig
Keyword(s):  
Material Properties ◽  
Object Oriented ◽  
The Finite Element Method ◽  
Simulation And Optimization ◽  
Gradient Based ◽  
Level Problem ◽  
Simulation Results ◽  
Optimization And Simulation ◽  
High Level ◽  
Simulation Parameters

Abstract In this paper we discuss the design of an object-oriented framework for simulation and optimization. Although oriented around high-level problem solving, the framework defines several classes of problems and includes concrete implementations of common algorithms for solving these problems. Simulations are run by combining these algorithms, as needed, for a particular problem. Included in this framework is the capability to compute the sensitivity of simulation results to the different simulation parameters (e.g. material properties, boundary conditions, etc). This sensitivity information is valuable in performing optimization because it allows the use of gradient-based optimization algorithms. Also included in the system are many useful abstractions and implementations related to the finite element method.

The Numerical Simulation of Effective Elastic Response for WC-Co Cemented Carbide

2015 ◽  
Vol 1096 ◽  
pp. 417-421
Author(s):  
Pei Luan Li ◽  
Zi Qian Huang
Keyword(s):  
Numerical Simulation ◽  
Finite Element Method ◽  
Finite Element ◽  
Theoretical Model ◽  
Material Properties ◽  
Cemented Carbide ◽  
Elastic Response ◽  
The Finite Element Method ◽  
Simulation Results ◽  
Element Method

By the use of finite element method, this paper predicts the effects of the shapes of reinforcements with different ductility (Co) on the effective elastic response for WC-Co cemented carbide. This paper conducts a comparative study on the material properties obtained through theoretical model, numerical simulation and experimental observations. Simulation results indicate that the finite element method is more sophisticated than the theoretical prediction.

Modelling and simulation of a sandwiched tube-type airbag and its optimization using design of experiments

2007 ◽  
Vol 221 (9) ◽  
pp. 1089-1095 ◽  
Author(s):  
J Huang ◽  
Z Zhong ◽  
L Hu ◽  
D Liu
Keyword(s):  
Optimization Design ◽  
Computational Modelling ◽  
The Finite Element Method ◽  
Simulation And Optimization ◽  
Design Variables ◽  
Mass Flowrate ◽  
New Type ◽  
Tube Type ◽  
Simulation Results ◽  
Modelling Simulation

This paper presents efforts made on the computational modelling, simulation, and optimization of a new type of airbag, namely a sandwiched tube-type airbag, which deploys more rapidly than the traditional airbag using less gas mass inflow and can decrease the risk of head injury of an out-of-position passenger. The airbag is modelled using the finite element method with MADYMO. A static airbag deployment test is performed to support and validate the computational modelling efforts. The considered variables for airbag optimization design are as follows: the collocation of the tether, the length of the tether, the mass flowrate, and the size and location of the vent hole. The simulation is performed using an orthogonal array, within the range of given control levels. Finally, the simulation results are analysed by iSIGHT, and the relationships between the design variables could help to design the airbag cushion.

scholarly journals Development of Elastoplastic-Damage Model of AlFeSi Phase for Aluminum Alloy 6061

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 954
Author(s):  
Hailong Wang ◽  
Wenping Deng ◽  
Tao Zhang ◽  
Jianhua Yao ◽  
Sujuan Wang
Keyword(s):  
Aluminum Alloy ◽  
Constitutive Model ◽  
Material Properties ◽  
Damage Model ◽  
Scratch Test ◽  
Aluminum Alloy 6061 ◽  
Ultra Precision ◽  
Simulation Results ◽  
Alloy 6061 ◽  
Elastoplastic Damage

Material properties affect the surface finishing in ultra-precision diamond cutting (UPDC), especially for aluminum alloy 6061 (Al6061) in which the cutting-induced temperature rise generates different types of precipitates on the machined surface. The precipitates generation not only changes the material properties but also induces imperfections on the generated surface, therefore increasing surface roughness for Al6061 in UPDC. To investigate precipitate effect so as to make a more precise control for the surface quality of the diamond turned Al6061, it is necessary to confirm the compositions and material properties of the precipitates. Previous studies have indicated that the major precipitate that induces scratch marks on the diamond turned Al6061 is an AlFeSi phase with the composition of Al86.1Fe8.3Si5.6. Therefore, in this paper, to study the material properties of the AlFeSi phase and its influences on ultra-precision machining of Al6061, an elastoplastic-damage model is proposed to build an elastoplastic constitutive model and a damage failure constitutive model of Al86.1Fe8.3Si5.6. By integrating finite element (FE) simulation and JMatPro, an efficient method is proposed to confirm the physical and thermophysical properties, temperature-phase transition characteristics, as well as the stress–strain curves of Al86.1Fe8.3Si5.6. Based on the developed elastoplastic-damage parameters of Al86.1Fe8.3Si5.6, FE simulations of the scratch test for Al86.1Fe8.3Si5.6 are conducted to verify the developed elastoplastic-damage model. Al86.1Fe8.3Si5.6 is prepared and scratch test experiments are carried out to compare with the simulation results, which indicated that, the simulation results agree well with those from scratch tests and the deviation of the scratch force in X-axis direction is less than 6.5%.

UML Based Design Approach for Storage System of Nano-Satellite

2014 ◽  
Vol 599-601 ◽  
pp. 530-533
Author(s):  
Hong Hao Wang ◽  
Hui Quan Wang ◽  
Zhong He Jin
Keyword(s):  
Storage System ◽  
Unified Modeling Language ◽  
Object Oriented ◽  
Modeling Language ◽  
Nand Flash ◽  
Unified Modeling ◽  
Object Oriented Design ◽  
High Level Modeling ◽  
High Level

Due to the complex timing sequence of NAND flash, a unified design process is urgently required to guarantee the reliability of storage system of nano-satellite. Unified Modeling Language (UML) is a widely used high level modeling language for object-oriented design. This paper adopts the UML as the design and modelling tool in the low level storage system design to elaborate the UML application in each phase of design in detail. The result shows taking UML as the modelling tool results in a clear and unambiguity design, which promotes the reliability and quality of software. At last, the feasibility of object-oriented implementation in C is presented.

A Two Step Damage Prognosis Method for Beam-Like Truss Structures

2014 ◽  
Vol 578-579 ◽  
pp. 1092-1095
Author(s):  
Hao Kai Jia ◽  
Ling Yu
Keyword(s):  
Finite Element Method ◽  
Strain Energy ◽  
Truss Structure ◽  
Truss Structures ◽  
Second Step ◽  
The Finite Element Method ◽  
Modal Strain Energy ◽  
Damage Prognosis ◽  
Modal Curvature ◽  
Simulation Results

In this study, a two step damage prognosis method is proposed for beam-like truss structures via combining modal curvature change (MCC) with modal strain energy change ratio (MSECR). Changes in the modal curvature and the elemental strain energy are selected as the indicator of damage prognosis. Different damage elements with different damage degrees are simulated. In the first step, the finite element method is used to model a beam-like truss structure and the displacement modes are got. The damage region is estimated by the MCC of top and bottom chords of a beam-like truss structure. In the second step, the elemental MSECR in the damage region is calculated and the maximum MSECR element is deemed as the damage element. The simulation results show that this method can accurately locate the damage in the beam-like truss structure.

A Novel Application of Gamification for Collecting High-Level Design Information

2015 ◽  
Author(s):  
Hyunmin Cheong ◽  
Wei Li ◽  
Francesco Iorio
Keyword(s):  
User Study ◽  
Design Knowledge ◽  
Cad Systems ◽  
Design Information ◽  
Knowledge Based ◽  
Game Mechanics ◽  
Abstract Level ◽  
Level Problem ◽  
Level Design ◽  
High Level

This paper presents a novel application of gamification for collecting high-level design descriptions of objects. High-level design descriptions entail not only superficial characteristics of an object, but also function, behavior, and requirement information of the object. Such information is difficult to obtain with traditional data mining techniques. For acquisition of high-level design information, we investigated a multiplayer game, “Who is the Pretender?” in an offline context. Through a user study, we demonstrate that the game offers a more fun, enjoyable, and engaging experience for providing descriptions of objects than simply asking people to list them. We also show that the game elicits more high-level, problem-oriented requirement descriptions and less low-level, solution-oriented structure descriptions due to the unique game mechanics that encourage players to describe objects at an abstract level. Finally, we present how crowdsourcing can be used to generate game content that facilitates the gameplay. Our work contributes towards acquiring high-level design knowledge that is essential for developing knowledge-based CAD systems.

scholarly journals Implementing Visual Analytics Pipelines with Simulation Data

2021 ◽  
Author(s):  
Taimur Khan ◽  
Syed Samad Shakeel ◽  
Afzal Gul ◽  
Hamza Masud ◽  
Achim Ebert
Keyword(s):  
Visual Analytics ◽  
Visual Analysis ◽  
Simulated Data ◽  
Evaluation Study ◽  
Ease Of Use ◽  
Preliminary Evaluation ◽  
Simulation Data ◽  
Visual Data Analytics ◽  
High Level ◽  
Simulation Parameters

Visual analytics has been widely studied in the past decade both in academia and industry to improve data exploration, minimize the overall cost, and improve data analysis. In this chapter, we explore the idea of visual analytics in the context of simulation data. This would then provide us with the capability to not only explore our data visually but also to apply machine learning models in order to answer high-level questions with respect to scheduling, choosing optimal simulation parameters, finding correlations, etc. More specifically, we examine state-of-the-art tools to be able to perform these above-mentioned tasks. Further, to test and validate our methodology we followed the human-centered design process to build a prototype tool called ViDAS (Visual Data Analytics of Simulated Data). Our preliminary evaluation study illustrates the intuitiveness and ease-of-use of our approach with regards to visual analysis of simulated data.

scholarly journals Uncertainty of the CO<sub>2</sub> threshold for melting a hard Snowball Earth

2010 ◽  
Vol 6 (4) ◽  
pp. 1337-1350 ◽  
Author(s):  
Y. Hu ◽  
J. Yang
Keyword(s):  
Greenhouse Effect ◽  
Atmospheric Model ◽  
Snowball Earth ◽  
Near Surface ◽  
Cloud Forcing ◽  
Clear Sky ◽  
Critical Issues ◽  
Simulation Results ◽  
High Level ◽  
Hadley Cells

Abstract. One of the critical issues of the Snowball Earth hypothesis is how high level of CO2 is required for triggering the deglaciation. Using Community Atmospheric Model version 3 (CAM3), we study the problem for the CO2 threshold. Our simulations show large differences from previous results (Pierrehumbert, 2004, 2005). At 0.2 bars of CO2, the January maximum near-surface temperature is about 268 K, about 13 K higher than that in Pierrehumbert (2004, 2005), but lower than the value of 270 K for 0.1 bar of CO2 in Le Hir et al. (2007). It is found that the diversity of simulation results is mainly due to model sensitivity of greenhouse effect and longwave cloud forcing to increasing CO2. At 0.2 bar of CO2, CAM3 yields 117 Wm −2 of clear-sky greenhouse effect and 32 Wm−2 of longwave cloud forcing, versus only about 77 Wm−2 and 10.5 Wm−2 in Pierrehumbert (2004, 2005), respectively. CAM3 has comparable clear-sky greenhouse effect to that in Le Hir et al. (2007), but lower longwave cloud forcing. CAM3 also produces much stronger Hadley cells than in Pierrehumbert (2005).

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