Thanh Tien Bui^1,*, Yoshihisa Fujita², Susumu Nakata²

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.2, pp. 425-442, 2021, DOI:10.32604/cmes.2021.016766 - 08 October 2021

Abstract In this paper, we propose a simplified approach of open boundary conditions for particle-based fluid simulations using the weakly compressible smoothed-particle hydrodynamics (SPH) method. In this scheme, the values of the inflow/outflow particles are calculated as fluid particles or imposed desired values to ensure the appropriate evolution of the flow field instead of using a renormalization process involving the fluid particles. We concentrate on handling the generation of new inflow particles using several simple approaches that contribute to the flow field stability. The advantages of the . -SPH scheme, specifically the particle shifting technique, were… More >

Xiangxi Du^*, Yanhua Sun

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.5, pp. 917-929, 2021, DOI:10.32604/fdmp.2021.015710 - 05 July 2021

Abstract A new type of foil bearings with a specific surface microstructure is studied. First, relevant boundary conditions based on the assumption of rarefied gas flow are proposed, then, the static bearing capacity and friction torque are analyzed in the framework of a numerical technique based on the discretization of the governing equation for rarefied gas-dynamics. It is shown that under the same static load, the difference between the minimum film thickness calculated in this exploration and the results provided by dedicated tests is not obvious; with an increase in the load, the simulation results are More >

A. Shahzad¹, W. A. Khan^2,*, R. Gul¹, B. Dayyan¹, M. Zubair¹

CMC-Computers, Materials & Continua, Vol.68, No.3, pp. 3877-3893, 2021, DOI:10.32604/cmc.2021.012524 - 06 May 2021

Abstract In this work, a steady, incompressible Williamson fluid model is investigated in a porous wavy channel. This situation arises in the reabsorption of useful substances from the glomerular filtrate in the kidney. After 80% reabsorption, urine is left, which behaves like a thinning fluid. The laws of conservation of mass and momentum are used to model the physical problem. The analytical solution of the problem in terms of stream function is obtained by a regular perturbation expansion method. The asymptotic integration method for small wave amplitudes and the RK-Fehlberg method for pressure distribution has been… More >

Zechen Yao¹, Renfeng Yang^1,*, Haichao An²

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.2, pp. 397-412, 2021, DOI:10.32604/fdmp.2021.012114 - 02 April 2021

Abstract Computational fluid dynamics (CFD) has been used to analyze the mixing process of Asphalt and Rubber (AR) in a stirred tank with a six flat-blade disc turbine (Rushton), a down-pumping 45° pitched-blade turbine (PBTD-6) and a down-pumping propeller (TXL). The two-phase (solid-liquid) flow in the considered stirred tank has been modelled in the framework of an Eulerian-Eulerian approach, a laminar-flow assumption and a multi-reference frame strategy. The following effects have been investigated: The influence of the impeller speed, impeller type, crumb rubber (CR) particle diameter and initial CR particle loading on the quality of the… More >

Sheng Bai, Feng Bao^*, Fengzhi Zhao, Miaomiao Liu

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.5, pp. 935-946, 2020, DOI:10.32604/fdmp.2020.010113 - 09 October 2020

Abstract The main objective of the present study is the development of a new algorithm that can adapt to complex and changeable environments. An artificial fish swarm algorithm is developed which relies on a wireless sensor network (WSN) in a hydrodynamic background. The nodes of this algorithm are viscous fluids and artificial fish, while related ‘events’ are directly connected to the food available in the related virtual environment. The results show that the total processing time of the data by the source node is 6.661 ms, of which the processing time of crosstalk data is 3.789… More >

Abdelraheem M. Aly^{1, 2, *}, Mitsuteru Asai³, Ehab Mahmoud Mohamed^{4, 5}

CMC-Computers, Materials & Continua, Vol.65, No.1, pp. 205-224, 2020, DOI:10.32604/cmc.2020.09227 - 23 July 2020

Abstract In the present work, an incompressible smoothed particle hydrodynamic (SPH) method is introduced to simulate water-soil-structure interactions. In the current calculation, the water is modelled as a Newtonian fluid. The soil is modelled in two different cases. In the first case, the granular material is considered as a fluid where a Bingham type constitutive model is proposed based on Mohr-Coulomb yield-stress criterion, and the viscosity is derived from the cohesion and friction angle. In addition, the fictitious suspension layers between water and soil depending on the concentration of soil are introduced. In the second case,… More >

Xiaofeng Yang^{1, *}, Yanhong Li¹, Aiguo Nie¹, Sheng Zhi², Liyuan Liu³

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.3, pp. 1141-1157, 2020, DOI:10.32604/cmes.2020.08538 - 01 March 2020

Abstract Supercritical carbon dioxide (Sc-CO₂) jet rock breaking is a nonlinear impact dynamics problem involving many factors. Considering the complexity of the physical properties of the Sc-CO₂ jet and the mesh distortion problem in dealing with large deformation problems using the finite element method, the smoothed particle hydrodynamics (SPH) method is used to simulate and analyze the rock breaking process by Sc-CO₂ jet based on the derivation of the jet velocity-density evolution mathematical model. The results indicate that there exisits an optimal rock breaking temperature by Sc-CO₂. The volume and length of the rock fracture increase with the… More >

M. Al-Saad¹, C. A. Suarez^{2, 4}, A. Obeidat², S. P. A. Bordas^{1, 2, 3, *}, S. Kulasegaram¹

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.3, pp. 831-862, 2020, DOI:10.32604/cmes.2020.08527 - 01 March 2020

Abstract Thrombosis plays a crucial role in atherosclerosis or in haemostasis when a blood vessel is injured. This article focuses on using a meshless particle-based Lagrangian numerical technique, the smoothed particles hydrodynamic (SPH) method, to study the flow behaviour of blood and to explore the flow parameters that induce formation of a thrombus in a blood vessel. Due to its simplicity and effectiveness, the SPH method is employed here to simulate the process of thrombogenesis and to study the effect of various blood flow parameters. In the present SPH simulation, blood is modelled by two sets More >

G. Nagaraju^a,∗ , Mahesh Garvandha^b, J.V. Ramana Murthy^c

Frontiers in Heat and Mass Transfer, Vol.13, pp. 1-8, 2019, DOI:10.5098/hmt.13.6

Abstract This paper analyzes a hypothesis of the 2−dimensional thermal transport behavior of Newtonian axisymmetric, viscous heating flow in a horizontal pipe. The flow is subjected to an externally applied uniform suction across the pipe wall in the polar direction, a constant magnetic field perpendicular to the wall and a uniform heat source/sink on the surface of the cylinder. The thermal boundary condition is imposed as a uniform heat flux. The Velocity fields are expressed in terms of stream function and the solution is obtained using the homotopy analysis method (HAM). Graphs are designed to analyze More >

Anupam Bhandari^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.15, No.5, pp. 557-582, 2019, DOI:10.32604/fdmp.2019.04108

Abstract The present research aims to examine the steady state of the two-dimensional incompressible magnetohydrodynamics (MHD) flow of a micropolar nanofluid over a stretching sheet in the presence of chemical reactions, radiation and viscous dissipation. The effect of particle rotation is taken into account. A conducting fluid passes over a semi-infinite plate with variable temperature while a magnetic field is directed in the transverse direction. Results for velocity, angular momentum, temperature and concentration profiles are obtained for various values of Eckert number, Schmidt number, Prandtl number, thermophosis parameter and Brownian motion parameters. A similarity approach is… More >