Chongfei Sun¹, Jianzhong Shang¹, Zirong Luo¹, Xin Li^2,*, Zhongyue Lu¹, Guoheng Wu¹

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.6, pp. 1147-1159, 2020, DOI:10.32604/fdmp.2020.09937

Abstract Small moving vehicles represent an important category of marine engineering tools and devices (equipment) typically used for ocean resource detection and maintenance of marine rights and interests. The lack of efficient power supply modes is one of the technical bottlenecks restricting the effective utilisation of this type of equipment. In this work, the performance characteristics of a new type of elastic-blade/wave-energy converter (EBWEC) and its core energy conversion component (named wave energy absorber) are comprehensively studied. In particular, computational fluid dynamics (CFD) simulations and experiments have been used to analyze the hydrodynamics and performance characteristics of the EBWEC. The pressure… More >

Zhenxin Zhao^1,#, Tong Chen^2,#, Xudong Liu³, Shengzhang Wang^2,4,*, Haiyan Lu^5,*

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.3, pp. 1173-1184, 2020, DOI:10.32604/cmes.2020.013702

Abstract In order to improve the surgical treatment of the congenital heart disease patient with single ventricle defect, two axial flow blood pumps, one with diffuser and the other without diffuser, were designed and virtually implanted into an idealized total cavopulmonary connection (TCPC) model to form two types of Pump-TCPC physiological structure. Computational fluid dynamics (CFD) simulations were performed to analyze the variations of the hemodynamic characteristics, such as flow field, wall shear stress (WSS), oscillatory shear index (OSI), relative residence time (RRT), between the two Pump-TCPC models. Numerical results indicate that the Pump-TCPC with diffuser has better flow field stability,… More >

Daiane Cristina Zanatta^1,*, Luciano Kiyoshi Araki², Marcio Augusto Villela Pinto², Diego Fernando Moro³

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.3, pp. 1061-1081, 2020, DOI:10.32604/cmes.2020.012634

Abstract This paper seeks to develop an efficient multigrid algorithm for solving the Burgers problem with the use of non-orthogonal structured curvilinear grids in L-shaped geometry. For this, the differential equations were discretized by Finite Volume Method (FVM) with second-order approximation scheme and deferred correction. Moreover, the algebraic method and the differential method were used to generate the non-orthogonal structured curvilinear grids. Furthermore, the influence of some parameters of geometric multigrid method, as well as lexicographical Gauss–Seidel (Lex-GS), η-line Gauss–Seidel (η-line-GS), Modified Strongly Implicit (MSI) and modified incomplete LU decomposition (MILU) solvers on the Central Processing Unit (CPU) time was investigated.… More >

Jungang Jia^*

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.5, pp. 919-933, 2020, DOI:10.32604/fdmp.2020.09566

Abstract To solve the problem of temperature rise caused by the high power density of high-speed permanent magnet synchronous traction motors, the temperature rise of various components in the motor is analyzed by coupling the equivalent thermal circuit method and computational fluid dynamics. Also, a cooling strategy is proposed to solve the problem of temperature rise, which is expected to prolong the service life of these devices. First, the theoretical bases of the approaches used to study heat transfer and fluid mechanics are discussed, then the fluid flow for the considered motor is analyzed, and the equivalent thermal circuit method is… More >

Donghua Dai^1,2, Dongdong Gu^1,2,*, Qing Ge^1,2, Chenglong Ma^1,2, Xinyu Shi^1,2, Han Zhang^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.3, pp. 1085-1098, 2020, DOI:10.32604/cmes.2020.010927

Abstract The three-dimensional physical model of the randomly packed powder material irradiated by the laser beam was established, taking into account the transformation of the material phase, the melt spreading and the interaction of the free surface of the molten pool and the recoiling pressure caused by the material evaporation during the selective laser melting. Influence of the processing parameters on the thermal behavior, the material evaporation, the surface morphology and the densification behavior in the connection region of the molten pool and the substrate was studied. It was shown that the powder material underwent the transformation from the partial melting… More >

Yi Wang^*, Mohan Lin

CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.3, pp. 885-914, 2020, DOI:10.32604/cmes.2020.09810

Abstract Due to the interaction and corrosion of the seawater, submarine pipelines are easy to be broken to spill oil. The special environment of subsea restricts the technical development of pipeline maintenance. Therefore, the study on the oil spilling model of submarine pipeline is very important for predicting the movement and diffusion of spilled oil, so that oil spilling traces and relating strategies can be determined. This paper aims to establish an oil spilling model of a submarine pipeline, study the movement characteristics of spilled oil in seawater by numerical simulation, and determine the traces, diffusion range, time to sea surface,… More >

Hao Cheng, Guangsheng Du^*, Meng Zhang, Kun Wang, Wenbin Bai

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.4, pp. 685-698, 2020, DOI:10.32604/fdmp.2020.09673

Abstract The determination of the circulation for wind turbine blades is an important problem in engineering. In the present study, we develop a specific approach to evaluate the integral that represents mathematically the circulation. First the potentialities of the method are assessed using a two-dimensional NACA64_A17 airfoil as a testbed and evaluating the influence of different integration paths and angles of attack on the circulation value. Then the method is applied to blades with different relative heights in order to provide useful reference data to be used for the optimization and reverse design of wind turbine blades. As shown by the… More >

Yuchi Kang^1,2, Meihong Liu¹, Sharon Kao‐Walter^2,3, Jinbin Liu¹, Qihong Cen⁴

Intelligent Automation & Soft Computing, Vol.25, No.2, pp. 405-411, 2019, DOI:10.31209/2019.100000102

Abstract A two-dimensional model of staggered tube banks of the bristle pack with different pitch ratios was solved by computational fluid dynamics (CFD). The pressure distribution along the gap centerlines and bristle surfaces were studied for different upstream pressure from 0.2 to 0.6MPa and models. The results show that the pressure is exponentially rather than strictly linearly decreasing distributed inside the bristle pack. The pressure distribution is symmetry about the circle’s horizontal line. The most obvious pressure drop occurred from about 60º to 90º. There is no stationary state reached between the kinetic energy and the static pressure when the upstream… More >

Di Wang¹, Guangzhao Ye¹, Jingming Mai², Xiaomin Chen¹, Yongqiang Yang^1,*, Yang Li^1,*, Xiaojun Chen¹, Jie Chen¹

CMES-Computer Modeling in Engineering & Sciences, Vol.123, No.3, pp. 1061-1077, 2020, DOI:10.32604/cmes.2020.09842

Abstract In this paper, a novel micromixer with complex 3D-shape inner units was put forward and fabricated by metal Additive Manufacturing (AM). The design of the micromixer combined the constraints of selective laser melting technology and the factors to improve mixing efficiency. Villermaux-Dushman reaction system and Compute Fluid Design (CFD) simulation were conducted to investigate the performance and the mechanism of this novel micromixer to improve mixing efficiency. The research found that the best mixing efficiency of this novel micromixer could be gained when the inner units divided fluid into five pieces with a uniform volume. Compared with a conventional micromixer… More >

Lennon Ó Náraigh^{1, *}, Daniel R. Jansen van Vuuren²

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.2, pp. 383-410, 2020, DOI:10.32604/fdmp.2020.09265

Abstract In this article we use analytical and numerical modeling to describe parallel viscous two-phase flows in microchannels. The focus is on idealized two-dimensional geometries, with a view to validating the various methodologies for future work in three dimensions. In the first instance, we use analytical Orr-Sommerfeld theory to describe the linear instability which governs the formation of small-amplitude waves in such systems. We then compare the results of this analysis with an in-house Computational Fluid Dynamics (CFD) solver called TPLS. Excellent agreement between the theoretical analysis and TPLS is obtained in the regime of small-amplitude waves. We continue the numerical… More >