Senchun Miao^1,2,*, Hongbiao Zhang¹, Wanglong Tian¹, Yinqiang Li²

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.6, pp. 1021-1036, 2021, DOI:10.32604/fdmp.2021.016925

Abstract To study the unsteady flow and related energy conversion process in the volute of a pump-as-turbine (PAT) device, six different working conditions have been considered. Through numerical calculation, the spatio-temporal variation of static pressure, dynamic pressure, total pressure and turbulent energy dissipation have been determined in each section of the volute. It is concluded that the reduction of the total power of two adjacent sections of the PAT volute is equal to the sum of the power lost by the fluid while moving from one section to the other and the power output from the two adjacent sections. For a… More >

Huinan Sun^1,*, Siqiang Wang², Zhuoqing Zhang¹, Chaoyong Xia¹, Xu Chen¹

CMES-Computer Modeling in Engineering & Sciences, Vol.127, No.3, pp. 855-873, 2021, DOI:10.32604/cmes.2021.015791

Abstract Grains are widely present in industrial productions and processing, and are stored in silos. In the silo, auxiliary structures are added to achieve efficient production. However, little effort has been devoted to the influence of the internal structure of the silo on the granular flow. In this work, a silo with a central decompression tube is studied through experimental measurements and discrete element methods. Then, the influences of the central decompression tube on the flow behavior of grains and wall pressure are analyzed. Results show that the grains are in mass flow in the silo without a central decompression tube,… More >

Yukun Lv, Quanzhi Ge^*, Zhuang Wei, Shuang Yang

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.4, pp. 833-844, 2021, DOI:10.32604/fdmp.2021.015082

Abstract The splitter is an important component of water-based cooling systems used to extract heat from computer boards. In the present study, the flow characteristics of a 16-splitter structure were numerically simulated and compared with experimental results to verify the reliability of the numerical simulation method. Accordingly, the concept of splitter structural coefficients was proposed. Based on the results of this study, we recommend a selection range of 5 ≤ k ≤ 6 for the structure factor k of the splitter; after optimization, the maximum deviation of the splitter outlet flow was reduced from the original value of 100% to 8.3%. More >

Ming Liu^1,2,3, Xingkai Zhang^1,4, Dong Wang^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.1, pp. 97-107, 2021, DOI:10.32604/fdmp.2021.011292

Abstract The mechanically choked orifice plate (MCOP) is a new type of device for flow control by which choking conditions for incompressible fluids can be obtained with relatively small pressure losses. Given the lack of relevant results and data in the literature, in the present study, we concentrate on the experimental determination of the flow coefficient for the annular orifice, the pressure distribution in the MCOP, and the characteristics of the choked flow itself. As confirmed by the experimental results, the Reynolds number, the orifice plate thickness, the plug taper, and the eccentricity have an obvious influence on the aforementioned flow… More >

Hongming Zhou^1,2, Haozheng Gao¹, Zheng Fang², Jiangxin Yang³, Mingge Wu^1,2,3,*

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.4, pp. 813-826, 2020, DOI:10.32604/fdmp.2020.010150

Abstract In order to grasp the particle flow characteristics and energy consumption of industrial fluidized spouted beds, we conduct numerical simulations on the basis of a Computational Particle Fluid Dynamics (CPFD) approach. In particular, the traction model of Wen-Yu-Ergun is used and different inlet conditions are considered. Using a low-speed fluidizing gas, the flow state of the particles is better and the amount of particles accumulated at the bottom of the bed wall becomes smaller. For the same air intake, the energy loss of a circular nozzle is larger than that of a square nozzle. More >

Tongjing Liu^{1, 2, *}, Weixia Liu³, Pengxiang Diwu⁴, Gaixing Hu^{5, 6}, Ting Xu^{1, 7}, Yuqi Li², Zhenjiang You⁸, Runwei Qiao², Jia Wang²

CMES-Computer Modeling in Engineering & Sciences, Vol.123, No.3, pp. 1205-1222, 2020, DOI:10.32604/cmes.2020.08961

Abstract Structure of porous media and fluid distribution in rocks can significantly affect the transport characteristics during the process of microscale tracer flow. To clarify the effect of micro heterogeneity on aqueous tracer transport, this paper demonstrates microscopic experiments at pore level and proposes an improved mathematical model for tracer transport. The visualization results show a faster tracer movement into movable water than it into bound water, and quicker occupancy in flowing pores than in storage pores caused by the difference of tracer velocity. Moreover, the proposed mathematical model includes the effects of bound water and flowing porosity by applying interstitial… More >

Lin Wang¹, Chunguo An², Nini Wang², Yaming Ping¹, Kun Wang¹, Ming Gao^1,*, Suoying He¹

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.3, pp. 585-600, 2020, DOI:10.32604/fdmp.2020.09611

Abstract Numerical simulation are conducted to explore the characteristics of the axial inflow and related aerodynamic noise for a large-scale adjustable fan with the installation angle changing from −12° to 12°. In such a range the maximum static (gauge) pressure at the inlet changes from −2280 Pa to 382 Pa, and the minimum static pressure decreases from −3389 Pa to −8000 Pa. As for the axial intermediate flow surface, one low pressure zone is located at the junction of the suction surface and the hub, another is located at the suction surface close to the casing position. At the outlet boundary,… More >

Zhihui Wang^1,2,3, Wei Luo^1,2,3,*, Ruiquan Liao^1,2,3, Xiangwei Xie⁴, Fuwei Han⁵, Hongying Wang⁶

FDMP-Fluid Dynamics & Materials Processing, Vol.15, No.5, pp. 583-595, 2019, DOI:10.32604/fdmp.2019.06847

Abstract Horizontal well production technology gradually occupies a dominant position in the petroleum field. With the rise in water production in the later stage of exploitation, slug flow phenomena will exist in horizontal, inclined and even vertical sections of gas wells. To grasp the flow law of slug flow and guide engineering practice, the flow law of slug flow at various inclination angles (30°~90°) is studied by means of the combination of laboratory experiments (including high frequency pressure data acquisition system) and finite element numerical simulation. The results reveal that because of the delay of pressure variation at the corresponding position… More >

Mingge Wu¹, Lei Wang¹, Yixiang Wang¹, Cheng Zhang¹, Cheng Qiu^{1, 2, *}

FDMP-Fluid Dynamics & Materials Processing, Vol.15, No.4, pp. 431-444, 2019, DOI:10.32604/fdmp.2019.08209

Abstract Water management in proton exchange membrane fuel cells (PEMFC) is a topic of great importance for the optimization of these systems. Effective proton conductivity calls for moderate moisture content in the membrane, while uneven water distribution can lead to instability of the whole flow field, thereby decreasing the performance of the fuel cell. In the present study, a simplified two-tier hybrid structure is used to investigate the impact of the dynamic behavior of liquid water on the current density of the PEMFC. Simulation results show that water droplets attached to wall sides tend to increase current density. Visualization experiments confirm… More >

Shunying Ji*, Siqiang Wang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.22, No.1, pp. 94-94, 2019, DOI:10.32604/icces.2019.04805

Abstract Granular flow is commonly encountered in industry or nature, and is significantly affected by particle shapes. Super-quadric particles which can construct the geometric shape of irregular particles are simulated by the Discrete Element Method (DEM). In this study, the influence of aspect ratio and blockiness of particles on the flow characteristics is investigated, and the different discharge angles are used for different shaped particles to show the superposed effect of hopper configuration. Meanwhile, the Lacey mixing index is used to explore the effects of particle shapes on the mixing and motion of the granular system in a horizontal rotating drum.… More >