Efficient parametric studies computations on grids and clouds with Civa software

A system of transcendental equations (SoTE) is a set of simultaneous equations containing at least a transcendental function. Solutions involving transcendental equations are often problematic, particularly in the form of a system of equations. This challenge has limited the number of equations, with inter-related multi-functions and multi-variables, often included in the mathematical modelling of physical systems during problem formulation. Here, we presented detailed steps for using a code-based modelling approach for solving SoTEs that may be encountered in science and engineering problems. A SoTE comprising six functions, including Sine-Gordon wave functions, was used to illustrate the steps. Parametric studies were performed to visualize how a change in the variables affected the superposition of the waves as the independent variable varies from x1 = 1:0.0005:100 to x1 = 1:5:100. The application of the proposed approach in modelling and simulation of photovoltaic and thermophotovoltaic systems were also highlighted. Overall, solutions to SoTEs present new opportunities for including more functions and variables in numerical models of systems, which will ultimately lead to a more robust representation of physical systems.

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A Finite Element Study on Compressive Resistance Degradation of Square and Circular Steel Braces under Axial Cyclic Loading

Applied Sciences ◽

10.3390/app11136094 ◽

2021 ◽

Vol 11 (13) ◽

pp. 6094

Author(s):

Hubdar Hussain ◽

Xiangyu Gao ◽

Anqi Shi

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Cyclic Loading ◽

Slenderness Ratio ◽

Hysteretic Behavior ◽

Element Analysis ◽

Section Shape ◽

Axial Cyclic Loading ◽

Global Buckling ◽

Parametric Studies

In this study, detailed finite element analysis was conducted to examine the seismic performance of square and circular hollow steel braces under axial cyclic loading. Finite element models of braces were constructed using ABAQUS finite element analysis (FEA) software and validated with experimental results from previous papers to expand the specimen’s matrix. The influences of cross-section shape, slenderness ratio, and width/diameter-to-thickness ratio on hysteretic behavior and compressive-tensile strength degradation were studied. Simulation results of parametric studies show that both square and circular hollow braces have a better cyclic performance with smaller slenderness and width/diameter-to-thickness ratios, and their compressive-tensile resistances ratio significantly decreases from cycle to cycle after the occurrence of the global buckling of braces.

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3D B-Rep meshing for real-time data-based geometric parametric analysis

Advanced Modeling and Simulation in Engineering Sciences ◽

10.1186/s40323-021-00194-5 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Tristan Maquart ◽

Thomas Elguedj ◽

Anthony Gravouil ◽

Michel Rochette

Keyword(s):

Real Time ◽

Surface Topology ◽

Time Data ◽

Standard Data ◽

Input Surface ◽

Cad Models ◽

Pants Decomposition ◽

Parametric Studies ◽

Geometry Feature ◽

Complicated Geometry

AbstractThis paper presents an effective framework to automatically construct 3D quadrilateral meshes of complicated geometry and arbitrary topology adapted for parametric studies. The input is a triangulation of the solid 3D model’s boundary provided from B-Rep CAD models or scanned geometry. The triangulated mesh is decomposed into a set of cuboids in two steps: pants decomposition and cuboid decomposition. This workflow includes an integration of a geometry-feature-aware pants-to-cuboids decomposition algorithm. This set of cuboids perfectly replicates the input surface topology. Using aligned global parameterization, patches are re-positioned on the surface in a way to achieve low overall distortion, and alignment to principal curvature directions and sharp features. Based on the cuboid decomposition and global parameterization, a 3D quadrilateral mesh is extracted. For different parametric instances with the same topology but different geometries, the MEG-IsoQuad method allows to have the same representation: isotopological meshes holding the same connectivity where each point on a mesh has an analogous one into all other meshes. Faithful 3D numerical charts of parametric geometries are then built using standard data-based techniques. Geometries are then evaluated in real-time. The efficiency and the robustness of the proposed approach are illustrated through a few parametric examples.

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Parametric Analysis on Landing Gear Strut Friction of Light Aircraft for Touchdown Performance

Applied Sciences ◽

10.3390/app11125445 ◽

2021 ◽

Vol 11 (12) ◽

pp. 5445

Author(s):

Shengyong Gan ◽

Xingbo Fang ◽

Xiaohui Wei

Keyword(s):

Response Surface ◽

Energy Absorption ◽

Landing Gear ◽

Surface Model ◽

Absorption Properties ◽

Surface Method ◽

Design Variables ◽

Landing Impact ◽

Landing Response ◽

Parametric Studies

The aim of this paper is to obtain the strut friction–touchdown performance relation for designing the parameters involving the strut friction of the landing gear in a light aircraft. The numerical model of the landing gear is validated by drop test of single half-axle landing gear, which is used to obtain the energy absorption properties of strut friction in the landing process. Parametric studies are conducted using the response surface method. Based on the design of the experiment results and response surface functions, the sensitivity analysis of the design variables is implemented. Furthermore, a multi-objective optimization is carried out for good touchdown performance. The results show that the proportion of energy absorption of friction load accounts for more than 35% of the total landing impact energy. The response surface model characterizes well for the landing response, with a minimum fitting accuracy of 99.52%. The most sensitive variables for the four landing responses are the lower bearing width and the wheel moment of inertia. Moreover, the max overloading of sprung mass in LC-1 decreases by 4.84% after design optimization, which illustrates that the method of analysis and optimization on the strut friction of landing gear is efficient for improving the aircraft touchdown performance.

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