T. Ahmed¹, S. Hassan^1,2, M. F. Hasan³, M. M. Molla^1,2,*, M. A. Taher⁴, S. C. Saha⁵

Energy Engineering, Vol.118, No.1, pp. 15-36, 2021, DOI:10.32604/EE.2020.011237

Abstract The magneto-hydrodynamics (MHD) effect is studied at different inclined angles in Rayleigh-Bénard (RB) convection inside a rectangular enclosure using the lattice Boltzmann method (LBM). The enclosure is filled with electrically conducting fluids of different characteristics. These characteristics are defined by Prandtl number, Pr. The considered Pr values for this study are 10 and 70. The influence of other dimensionless parameters Rayleigh numbers Ra = 10³; 10⁴; 10⁵; 10⁶ and Hartmann numbers Ha = 0, 10, 25, 50, 100, on fluid flow and heat transfer, are also investigated considering different inclined angles φ of magnetic field by analyzing computed local Nusselt… More >

Cong Qi^1,2,*, Chengchao Wang^1,2, Jinghua Tang^1,2, Dongtai Han²

Energy Engineering, Vol.117, No.2, pp. 63-78, 2020, DOI:10.32604/EE.2020.010433

Abstract Because of the poor thermal performance of ordinary tubes, a triangular tube was used to replace the smooth channel in the heat transfer system, and nanofluids were used to take the place of ordinary fluids as the heat transfer medium. High stability nanofluids were prepared, and an experimental set on flow and heat exchange was established. Effects of triangular tube rotation angles (α = 0°, 30°, 60°) as well as mass fractions of nanofluids (ω = 0.1%, 0.3%, 0.5%) on heat exchange and flow performance were experimentally considered at Reynolds numbers (Re = 800–8000). It was shown that the triangular… More >

Baichun Gong¹, Shuang Li^{1, *}, Lili Zheng², Jinglang Feng³

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.1, pp. 221-234, 2020, DOI:10.32604/cmes.2020.07769

Abstract A closed-form solution to the angles-only initial relative orbit determination (IROD) problem for space rendezvous with non-cooperated target is developed, where a method of hybrid dynamics with the concept of virtual formation is introduced to analytically solve the problem. Emphasis is placed on developing the solution based on hybrid dynamics (i.e., Clohessy-Wiltshire equations and two-body dynamics), obtaining formation geometries that produce relative orbit state observability, and deriving the approximate analytic error covariance for the IROD solution. A standard Monte Carlo simulation system based on two-body dynamics is used to verify the feasibility and evaluate the performance proposed algorithms. The sensitivity… More >

D. Shaw, W.L. Su

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.3, pp. 85-86, 2011, DOI:10.3970/icces.2011.018.085

Abstract The contact angle affects the life and accuracy of a linear gudieway. In this study, the factors which effect the angle of contact angle of linear guideway includes contact deformation of balls and grooves, downward load, ball diameter, number of load-carrying balls, number of load-carrying rows and conformity. A theoretical approach for finding the contact angle changed of linear gudieway is proposed by using Hertzian theory and Lundeberg/Palmgren approach. The results are useful for modification of loading capability of linear gudieway under load and different preload setting. More >

R. A. Tough^1,2, A. M. Tousi², J. Ghaffari²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.14, No.1, pp. 1-22, 2010, DOI:10.3970/icces.2010.014.001

Abstract In this paper, micro-turbine centrifugal impeller with three different blade angles was investigated by using Computational Fluid Dynamics (CFD) method. The other basic geometric parameters are held constant. The influence of the blade angles change on the observed values was determined from numerical solution of the flow in the impeller with help of the FLUENT software. The numerical simulation focused on the air flow from compressor impeller inlet to exit, and the performance of impeller is predicted. The numerical solution was performed for original impeller geometry and for two other cases, in which blade inlet angle and backward sweep was… More >

Emil Budescu¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.11, No.1, pp. 17-18, 2009, DOI:10.3970/icces.2009.011.017

Abstract For the visco-plastic materials of type Bingham fluid, like granular materials, the process of flow begins when the force F^ˉ, which variation is presented in figure 1, reaches the minimum value of shearing limit. More >

Tushar Kulkarni¹, Dr. Rashmi Uddanwadiker²

Molecular & Cellular Biomechanics, Vol.13, No.2, pp. 87-104, 2016, DOI:10.3970/mcb.2016.013.099

Abstract This paper aims to determine the force required for holding the objects by human hand. A static analysis is performed on mathematical models to obtain holding force considering lower arm as class three lever and by varying the joint angles. Three mathematical models are discussed to quantify the force required to hold any object, for different weight of the object and the joint angles. A noninvasive experimentation using surface electromyogram was performed to determine the forces required by human hand for the same objects used in the mathematical modeling. Twenty-one male subjects participated in this test and were asked to… More >

V. Vavourakis ¹

CMES-Computer Modeling in Engineering & Sciences, Vol.36, No.2, pp. 119-146, 2008, DOI:10.3970/cmes.2008.036.119

Abstract In this paper, a new meshless Local Hypersingular Boundary Integral Equation method is presented for the analysis of two-dimensional elastostatic problems. The elastic domain is discretized by placing arbitrarily nodes on its boundary and interior. Given this set of nodes, the corresponding map of background triangles is constructed through a common triangulation algorithm. The local domain of each node consists of the union of triangles that this point lies, thus, creating a polygonal line of its local boundary. The local boundary integral equations of both displacements and stresses of the conventional Boundary Elements Method are taken into account. The interpolation… More >

C.S. Nor Azwadi¹, N.I.N. Izual²

CMES-Computer Modeling in Engineering & Sciences, Vol.84, No.6, pp. 559-574, 2012, DOI:10.3970/cmes.2012.084.559

Abstract Natural convection in a differentially heated enclosure plays vital role in engineering applications such as nuclear reactor, electronic cooling technologies, roof ventilation, etc. The developed thermal flow patterns induced by the density difference are expected to be critically dependence on the inclination angles of the cavity. Hence, thermal and fluid flow pattern inside a differentially heated side enclosure walls with various inclination angles have been investigated numerically using the mesoscale lattice Boltzmann scheme. Three different dimensionless Rayleigh numbers were used, and a dimensionless Prandtl number of 0.71 was set to simulate the circulation of air in the system. It was… More >

Humihiko Gotou¹, Takashi Kuwataka¹, Terumasa Nishihara¹, Tetsuo Iwakuma¹

CMES-Computer Modeling in Engineering & Sciences, Vol.4, No.2, pp. 319-328, 2003, DOI:10.3970/cmes.2003.004.319

Abstract The stiffness equation in finite displacement problems is often derived from the virtual work equation, partly in order to avoid the complicated formulation based on the potential functional. Describing the virtual rotational angles by infinitesimal rotational angles about three axes of the right-angled Cartesian coordinate system, we formulate tangent stiffness equations whose rotational degrees of freedom are described by rotational angles about the three axes. The rotational degrees of freedom are useful to treat three rotational components in nodal displacement vectors as vector components for coordinate transformation, when non-vector components like Euler's angles are used to describe finite rotations. In… More >