Jian Hua Rong^1,2,3, Zhi Jun Zhao⁴, Yi Min Xie⁵, Ji Jun Yi^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.90, No.3, pp. 211-231, 2013, DOI:10.3970/cmes.2013.090.211

Abstract Similar periodic structures have been widely used in engineering. In order to obtaining the optimal similar periodic structures, a topology optimization method of similar periodic structures with multiple displacement constraints is proposed in this paper. Firstly, in the proposed method, the design domain is divided into sub-domains. Secondly, a penalty term considering discrete conditions of density variables is introduced into the objective function, and the reciprocal density exponents of structural elements are taken as design variables. A topological optimization model of a similar periodic continuum structure with the objective function being the structural mass and More >

Zonglu Guo¹, Deli Gao¹

CMES-Computer Modeling in Engineering & Sciences, Vol.90, No.1, pp. 65-76, 2013, DOI:10.3970/cmes.2013.090.065

Abstract The modeling of the bottomhole assembly (BHA) is an essential problem in directional drilling. Some basic equations for predicting the performance of the BHA are presented in this paper. These equations take into account the effects of the axial displacement. The method of weighted residuals and the Newton-Raphson iterations are used to compute the nonlinear effects of the deformation of the BHA. A computer program is developed for the analysis of the BHA in order to quantitatively predict the performance of the BHA in directional drilling. In addition, a case study is presented to evaluate More >

D. Bergmair^1,2, S. J. Metz¹, H. C. de Lange², A. A. van Steenhoven²

CMES-Computer Modeling in Engineering & Sciences, Vol.91, No.1, pp. 1-15, 2013, DOI:10.3970/cmes.2013.091.001

Abstract A method to predict the permeation of water vapor, present in a laminar flowing humid carrier gas, through a hollow fiber membrane is presented. The method uses simulation particles that move like molecules, according to the kinetic gas theory, but carry the physical properties of an ensemble of molecules which they statistically represent. With this approach an ideal operational window for membrane modules can be found and parameters tested for, can be varied over orders of magnitude. The results show that the right dimensioning is essential for the efficient use of the membrane area. More >

L. N. McCartney¹

CMC-Computers, Materials & Continua, Vol.35, No.3, pp. 183-227, 2013, DOI:10.3970/cmc.2013.035.183

Abstract Analytical stress transfer models are described that enable estimates to be made of the stress and displacement fields that are associated with fibre fractures or matrix cracks in unidirectional fibre reinforced composites. The models represent a clear improvement on popular shear-lag based methodologies. The model takes account of thermal residual stresses, and is based on simplifying assumptions that the axial stress in the fibre is independent of the radial coordinate, and similarly for the matrix. A representation for both the stress and displacement fields is derived that satisfies exactly the equilibrium equations, the required interface… More >

Yi Xiao¹, Qing H. Qin¹

CMC-Computers, Materials & Continua, Vol.34, No.2, pp. 95-115, 2013, DOI:10.3970/cmc.2013.034.095

Abstract In this paper, we propose a new approach of optical full-field measurement for displacement calculation on the surface of a cellular solid. Cell boundary points are sampled as nodes in the analysis. To find the nodal values of displacements the nodes are to be mapped onto their corresponding points in the deformed cell boundary by shape based point matching. A thin plate spline based robust point matching (TPS-RPM) approach is used instead of correlation of intensity pattern between two regions in traditional displacement measurement methods. The proposed approach involves multiple-step image processing including cell region More >

Zaobao Liu^1,2, Weiya Xu¹, Jianfu Shao²

CMES-Computer Modeling in Engineering & Sciences, Vol.84, No.2, pp. 99-122, 2012, DOI:10.3970/cmes.2012.084.099

Abstract In this paper, the Gauss process is proposed for application on landslide displacement analysis and prediction with dynamic crossing validation. The prediction problem using noisy observations is first introduced. Then the Gauss process method is proposed for modeling non-stationary series of landslide displacements based on its ability to model noisy data. The monitoring displacement series of the New Wolong Temple Landslide is comparatively studied with other methods as an instance to implement the strategy of the Gauss process for predicting landslide displacement. The dynamic crossing validation method is adopted to manage the displacement series so… More >

Hyung-Jo Jung, Jong-Jae Lee, Jeong-Su Park

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 125-126, 2011, DOI:10.3970/icces.2011.019.125

Abstract A vision-based displacement measurement method for structural health monitoring of large-scale infrastructures such as high-rise buildings and long-span bridges is presented. The method uses digital image processing techniques including a target recognition algorithm, projection of the captured image, and calculation of the actual displacement using target geometry and the number of pixels moved. To measure the displacement of a flexible structure from a distant location which can be regarded as a fixed reference point, a novel image processing method has been devised by means of successive estimation of relative displacement and rotational angle using a More >

Guo Baoqiao, Chen Pengwan, Zhang Qingming, Li Yanjie, Xie Huimin

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.4, pp. 115-116, 2011, DOI:10.3970/icces.2011.017.115

Abstract Optical full-field measurement methods are now widely applied in various domains. In general, the displacement fields can be directly obtained from the measurement; however in mechanical analysis strain fields are preferred. To extract strain fields from noisy displacement fields is always a challenging topic. In this study, a finite element method for smoothing displacement fields and calculating strain fields is proposed. An experimental test case on a holed aluminum specimen under tension is applied to validate this method. The heterogeneous displacement fields of the area around the hole are measured by the digital image correlation More >

Ping Hu, Yang Xia, Limin Tang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.3, pp. 75-76, 2011, DOI:10.3970/icces.2011.017.075

Abstract In this paper, a modified paradigm of quasi conforming finite element method with truncated polynomial expansions of in-domain displacements and derived expansions of strains is introduced. The purpose is to improve the drawbacks of the traditional one that neglecting the connections between the components of strain and lack of principle in the process of choosing polynomial expansions. Based on the modified framework a four-node quadrilateral flat shell element with complete quadratic polynomials for membrane and bending displacement fields is developed. Numerical tests are carried out for validation of the present element. The results show that More >

K.C. Chuang, C.C. Ma, C.H. Wang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.1, pp. 1-2, 2011, DOI:10.3970/icces.2011.019.001

Abstract Smart flexible structures involve four key elements: actuators, sensors, control strategies, and power conditioning electronics, which makes the structures being capable of realizing specific functions. Recently, fiber Bragg grating (FBG) strain sensors are being considered to be integrated into smart structures since they possess many excellent properties such as low density, small size, simplicity of fabrication, and immunity to electromagnetic fields. In this paper, unlike traditional FBG strain sensors, a fiber Bragg grating (FBG) sensing system which has the ability to detect point-wise out-of-plane displacement responses is set up on a smart cantilever beam to… More >