Papers by Keyword: Mesh Size

Abstract: A 2-D finite volume Computational Fluid Dynamic (CFD) model, using Ansys Fluent vR.1 of a vertically oriented upwards continuous casting (VUCC), was investigated for 8 mm, oxygen free copper (OFCu). The simulations enabled the mapping of the cast OFCu solidification front (SF) interface from liquid to solid. Optimisation of the simulation parameters were investigated which included mesh size and the Ansys specific ‘mushy zone’ constant (A_mush), which is used to account for fluid flow dampening at SF within the model. Observations of the SF, the change in fluid volume in the die, the simulation convergence and the total simulation time, revealed that the optimised casting parameters were for mesh size 1×10^-4 m and A_mush 10⁶ kg/m³s. These parameters were compared with the cast rod and highlighted qualitatively the relationship between grain growth direction and SF position during a casting pulse cycle.

Abstract: This paper focuses on the works to model the aluminium honeycomb with the effect of meshing size that implemented into a shell body of the honeycomb and frictional force that introduced into an interaction between the honeycomb and rigid plates. The model is performed by using ABAQUS 6.12 in the explicit environment. The honeycomb with 0.0127 m cell size is modelled and three types of mesh size which are 3 mm, 1 mm and 0.8 mm are analysed based on buckling mode and load-displacement characteristics. No friction coefficient is applied during simulation. From this simulation, 1 mm meshing size is the optimize value where the load-compression pattern graph is almost similar like the experimental result compared with others meshing size. But the buckling mode is slightly different compared with the experimental result where the bottom part of honeycomb made the contract or negative expand behaviour. In order to avoid this behaviour, the friction coefficient is introduced between the honeycomb surface and rigid plates surface. Two values of friction coefficient are tested which are 0.1 and 0.3. The findings is the frictional coefficient 0.3 and meshing size 1 mm are optimized values that can avoid the contract behaviour and the result of buckling mode is similar with the experimental result.

Abstract: The nonlinear finite element can precisely simulate practical work condition of arch dam, but also has some problems in the safety evaluation of high arch dam, mainly in different mesh size, different strength criteria and constitutive relations of dam corresponding to different results. This article first proposes determining method for reasonable mesh size describes three strength criterions of uniaxial, biaxial, triaxial, gives two constitutive relations of dam cracking, damage. Take a high arch dam as an example, has done some research on the above question, obtain some beneficial conclusions.

Abstract: Surface finish and Manufacturing process has a prominent role in the fatigue life of a machine component. Fatigue strength of a material generally increases with the surface finish. But the super finishing process like electro polishing reduces the fatigue strength of the material. In Abrasive flow machining it is found that surface finish and fatigue strength always increasing. In Abrasive flow machining the fatigue strength is mainly governed by the process variables extrusion pressure, abrasive concentration and mesh size. This research studies the influence of the process variables on the fatigue strength of the material. In this study an approximate surface finish of 4μm is obtained after AFM. The effect of three process variables on the response function selected, fatigue strength, were studied. A statistical 2³ full factorial experimental technique is used to find out the main effect, interaction effect and contribution of each variable on fatigue strength. The instron machine is used to find out the number of cycles to failure of the material. The fatigue strength is obtained with S-N curve analysis.

Abstract: The cylinder for experiment has been excited by steady sinusoidal and random white noise excitation forces and the acceleration responses are measured. The frequency response functions of two excitation ways agree well. The reciprocity law and the linearity are certified by exchanging the excitation and measurement spots and increasing input voltage continuously respectively. The influence of mesh size to calculated time and precision of vacuum vibration mean square velocity and underwater vibration mean square velocity and acoustic radiation are investigated. Results show that time consumed mounts with the mesh size gets smaller, and the vibroacoustic results is less influenced at lower frequencies but much more at higher frequencies.

Abstract: This paper contains the results of an investigation into the effect of the discretization of lattice models. The study is performed with homogeneous models where all elements share the same strength. Elemental constitutive law is linearly-brittle, meaning that elements behave linearly but are completely removed from the structure as soon as they reach the limit of their strength. The relation between structural size and discretization density is studied with unnotched beams loaded in three point bending (modulus of rupture test). We report the results for regular discretization and irregular networks obtained via Voronoi tessellation. This is carried out for two types of models: these being with and without rotational springs (normal and shear springs are always present). The numerically obtained dependence of strength on discretization density is compared to the analytical size effect formula.

Abstract: In the simulation, the mesh quality has a significant impact on the simulation results. To study the influence of the size and shape of target mesh on the high velocity projectile penetration into concrete, using ANSYS/LS-DYNA software in this paper, different target mesh side lengths are selected to simulate, the variation curve that depth of penetration (DOP) with target mesh side length is obtained, select 1/6 times projectile radius as the target mesh side length can meet the accuracy requirements. Based the target mesh side length above, different radios of the mesh side length in the radial direction to the side length in the axial direction are selected to simulate, the influence law of calculating results that depend on the mesh shape is acquired. The contrast validation of experimental results is carried out, the simulation results are in agreement with the experimental results.

Abstract: A variety of parametric studies utilizing the finite element analysis (FEA) have been performed by Kim et al in order to predict the mechanical behavior(ultimate strength) of single shear bolted joints in cold-formed(thin-walled) stainless steel. The precedent researches have been conducted with respect to the mechanical behaviors of single shear bolted joints fabricated with four bolts and two bolts. Subsequently, this study has been focused on the comparison of ultimate behaviors between the existing test results and FEA results. In addition, parametric study has been performed in order to investigate the influence of mesh size and washer existence on ultimate behaviors. Therefore, reasonable finite element modelling method and condition were recommended in this paper.

Abstract: In order to solve two problems when simulating the phenomenon of Shaped Charge Liner penetrating into target, an example was simulated to study the influence of mesh size and target dimension on the penetration results using AUTODYN-2D. The relationship between the Shaped Charge Liner parameters and the critical dimension of the target was gained．The effects of mesh sizes on the penetration depth, aperture，and calculation time were studied. After analyzing the simulation results，a proper range of mesh size was obtained. The simulation results agree well with the test results. The research could provide reference on the simulation of Shaped Charge Liner.