Leone Corradi¹, Francesco Genna²

CMES-Computer Modeling in Engineering & Sciences, Vol.4, No.3&4, pp. 381-396, 2003, DOI:10.3970/cmes.2003.004.381

Abstract A critical comparison of several Finite Element models is presented, with reference to the analysis of the stress and strain states around a tooth or a fixed dental implant. Such an analysis, if performed on a full, three-dimensional geometry of the jaw-tooth/dental implant system, requires significant computational resources, and it is therefore often done on simplified models, whose validity can be questionable. On the other side, the use of simplified models is adequate --- almost mandatory --- when detailed results are needed, or when geometrical and material nonlinearities, as well as other complicating factors, are to be taken into account.… More >

S.H. Ju¹

CMES-Computer Modeling in Engineering & Sciences, Vol.64, No.1, pp. 91-109, 2010, DOI:10.3970/cmes.2010.064.091

Abstract This study develops an OpenMP scheme to parallel the preconditioned conjugate gradient methods (PCG) in shared memory computers. The proposed method is simple and systematic, so a minor change in traditional PCG methods may produce effective parallelism. At first, the global stiffness matrix is re-numbered in order to produce a parallel three-line form matrix, and a subroutine only needs to be called once in the finite element analysis. Several basic OpenMP commands are then added into the traditional incomplete Cholesky factorization (ILU) and symmetric successive over-relaxation (SSOR) codes to make the procedures of matrix multiplication, decomposition, forward substitution, and backward… More >

Kun Peng¹, Aike Qiao^1,*, Makoto Ohta², Narendra Kurnia Putra², Xinyang Cui¹, Yongliang Mu³, Hitomi Anzai²

CMES-Computer Modeling in Engineering & Sciences, Vol.117, No.1, pp. 17-28, 2018, DOI:10.31614/cmes.2018.04113

Abstract Biodegradable zinc alloy stents are a prospective solution for complications caused by the incompatibility between artery and permanent stents. However, insufficient scaffolding has limited the clinical application of biodegradable zinc alloy stents. Therefore, in this study, a new stent concept was designed to improve the scaffolding. The mechanical performances of the new and a traditional design stent were investigated and compared using finite element analysis (FEA). The new and traditional design stent were expanded to the intended radial displacement of 0.24 mm under the expansion pressure of 0.58 MPa and 0.45 MPa, respectively. Then, a pressure load of 0.35 MPa… More >

G. Suguinoshita¹, C. H. Silva¹, M. A. Luersen^{1, *}

CMES-Computer Modeling in Engineering & Sciences, Vol.117, No.1, pp. 59-71, 2018, DOI:10.31614/cmes.2018.01777

Abstract This paper describes a study of the effects of graphite nodule characteristics on a subsurface crack in austempered ductile iron (ADI). A representative specimen of ADI, subjected to sliding contact load, is modeled using finite elements aiming to obtain the shear stress intensity factor (K_II). The parameters varied were (i) the nodule diameter (two different values were considered), (ii) the distance between the nodule and the tip of the crack and (iii) the position of the load relative to the tip of the crack. The results of the numerical simulations show that the smaller diameter nodule has a larger influence… More >

Lei Peng^1,2, Zhiqiang Feng^1,2,*, Pierre Joli², Christine Renaud²

CMES-Computer Modeling in Engineering & Sciences, Vol.118, No.1, pp. 111-137, 2019, DOI:10.31614/cmes.2018.04556

Abstract In order to investigate the mechanical behavior of systems with complex architecture and a large number of contacting bodies, a finite element software, named LiToTac, has been developed by using the object-oriented programming technique. This software, with an interactive graphical user interface, is able to handle highly non-linear problems including multiple contacts and large deformation. More importantly, the contact detection based on a hybrid three-stages methodology can be performed automatically, which is more efficient than the common strategies of pre-defining contact zones in commercial FEM software like ANSYS, ABAQUS, etc. In addition, the contact solver in LiToTac is portable between… More >

Ji Wang, Yangyang Chen, Guijia Chen, Jianke Du

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.3, pp. 89-90, 2011, DOI:10.3970/icces.2011.017.089

Abstract The finite element analysis of quartz crystal resonators is increasingly important due to the precise design requirements in frequency and electrical properties with the consideration of crystal blank, processing, mounting, and packaging. To reduce the computational cost, one proven approach is to use the Mindlin plate theory for the thickness-shear vibrations of crystal plates with electrodes and other complications. This approach has been implemented in parallel finite element method with the sophisticated software components for the solutions of linear systems in terms such as eigenvalues, mode shapes, and amplitudes, which in turn can be used for the evaluation of certain… More >

R. Muhammad*, A. Maurotto, M. Demiral, A. Roy and V.V. Silberschmidt

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.3, pp. 95-96, 2011, DOI:10.3970/icces.2011.019.095

Abstract Analysis of the cutting process in machining of modern engineering materials (Ti- and Ni-based alloys), which are hard-to-cut materials, is a challenge that needs to be addressed. Machining of these alloys with conventional techniques is difficult and often results in tool failure due to the high cutting forces imposed on the tool. In a machining operation, cutting forces causes severe deformations in the proximity of the cutting edge, producing high stresses, strain, strain-rates and temperatures in the workpiece.
Ultrasonically assisted turning (UAT) is an advanced machining process, which has shown several advantages especially in the machining of high strength… More >

Yuan Weifeng, Tan Kang Hai

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.1, pp. 15-16, 2011, DOI:10.3970/icces.2011.018.015

Abstract Generally, the computational efficiency in numerical analysis is dependant on the degree of freedom in the model under investigation. To reduce computational cost without altering the accuracy of numerical findings, an algorithm is introduced in this manuscript to develop macro element. When this method is incorporated into finite element analysis, all the members in the nonlinear zones of a structure can be grouped into just one macro element. With the presence of weak member method, the stiffness matrix of this macro element can be evaluated through analyzing the response of the original structure induced by a series of fictitious unit… More >

CHEN Cheng, SHAO Yongbo, YANG Jie

The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 117-118, 2011, DOI:10.3970/icces.2011.016.117

Abstract A group of finite element models, reinforced circular hollow section (CHS) T-joints, are established to investigate the fire resistance compared with the un-reinforced by using finite element program ABAQUS in this paper. Sequentially coupled thermal-stress analysis is used to simulate the process of tubular T-joint under different loading levels in the condition of fire. The heat properties of the steel use the specified values in Eurocode 3. The fire resistance performance of collar plate reinforce CHS T-joints and the un-reinforced models are studied under different loading levels. The applied loads are 20%, 40%, 60% and 80% of the static strength… More >

Bingyu Ni, Chao Jiang^*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.21, No.4, pp. 91-91, 2019, DOI:10.32604/icces.2019.05517

Abstract Uncertain parameters with inherent spatial variability are commonly encountered in engineering. These include material properties of the heterogeneous media such as concrete or porous rock, external loads such as wind or snow loads applied on structures, etc. This type of uncertain parameters is traditionally quantified by the random field model, while the large amount of information required in construction of the precise probability distribution functions is often difficult to obtain for many practical engineering problems. The authors propose an interval field model to represent the spatial uncertainties with insufficient information, in which the variation of the parameter at any location… More >