Zongkai Liu^1,2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.2, pp. 427-439, 2021, DOI:10.32604/fdmp.2021.010528 - 02 April 2021

Abstract The so-called surface Magneto-hydro-dynamic (MHD) propulsion relies on the Lorentz force induced in weak electrolyte solutions (such as seawater or plasma) by NdFeB Magnets. The Lorentz force plays an important role in such dynamics as it directly affects the structures of flow boundary layers. Previous studies have mainly focused on the development of such boundary layers and related fluid-dynamic aspects. The main focus of the present study is the determination of electromagnetic field distributions around the propulsion units. In particular dedicated experiments and numerical simulations (based on the finite volume method) are conducted considering a More >

Ke Sun, Xiaoyu Hu, Da Li, Guodong Zhang, Kui Zhao, Haiyang Zhao, Shuzhan Bai^*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.1, pp. 81-95, 2021, DOI:10.32604/fdmp.2021.013895 - 09 February 2021

Abstract Experiments on subcooled flow boiling have been conducted using water in a rectangular flow channel. Similar to the coolant channel in internal combustion engines (IC engines), the flow channel in this experiment was asymmetrically heated. Bubble images were captured using a high speed camera from the side view of the channel. The experimental conditions in terms of bulk temperature, bulk velocity, pressure and heat flux ranged from 65°C–75°C, 0.25 m/s–0.75 m/s, 1–1.7 bar and 490 kW/m²–700 kW/m², respectively. On the basis of these tests, a statistical analysis of the bubble size has been conducted considering a More >

Khadija A. Al-Hassani¹, M. S. Alam², M. M. Rahman^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.1, pp. 1-20, 2021, DOI:10.32604/fdmp.2021.013497 - 09 February 2021

Abstract Nanofluids have enjoyed a widespread use in many technological applications due to their peculiar properties. Numerical simulations are presented about the unsteady behavior of mixed convection of Fe₃O₄-water, Fe₃O₄- kerosene, Fe₃O₄-ethylene glycol, and Fe₃O₄-engine oil nanofluids inside a lid-driven triangular cavity. In particular, a two-component non-homogeneous nanofluid model is used. The bottom wall of the enclosure is insulated, whereas the inclined wall is kept a constant (cold) temperature and various temperature laws are assumed for the vertical wall, namely: θ = 1(Case 1), θ = Y(1 – Y)(Case 2), and θ = sin(2πY)(Case 3). A tilted magnetic field of More >

Shidan Chi¹, Tao Luan^1,*, Yan Liang², Xundong Hu², Yan Gao^3,*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.1, pp. 71-80, 2021, DOI:10.32604/fdmp.2021.013178 - 09 February 2021

Abstract Improving the primary steam parameters is one of the most direct ways to improve the cycle efficiency of a power generation system. In the present study, the typical problem connected to the excessively high superheat degree of extraction steam in an ultra-supercritical (USC) double-reheat unit is considered. Using a 1000 MW power plant as an example, two systems (case 1 and case 2) are proposed, both working in combination with a regenerative steam turbine. The thermal performances of these two systems are compared with that of the original system through a heat balance method and More >

Senchun Miao^1,2,*, Hongbiao Zhang¹, Fengxia Shi¹, Xiaohui Wang¹, Xijin Ma¹

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.1, pp. 201-214, 2021, DOI:10.32604/fdmp.2021.012950 - 09 February 2021

Abstract A volute is a curved funnel with cross-sectional area increasing towards the discharge port. The volute of a centrifugal pump is the casing hosting the fluid being pumped by the impeller. In Pump-as-turbine devices (PAT), vice versa the volute plays the role of energy conversion element. In the present analysis, this process is analyzed using CFD. The results show that in the contraction section of volute the conversion between dynamic pressure energy and static pressure energy essentially depends on the reduction of flow area, while in the spiral section, frictional losses also play a significant More >

Siqi Liu^1,2,3, Guanqi Huang^3,4,*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.1, pp. 141-157, 2021, DOI:10.32604/fdmp.2021.011990 - 09 February 2021

Abstract Many countries in the world have experienced extremely rapid urbanization during recent decades. The rapid development of densely populated areas has produced many urban environmental problems. This research explores the relationship between urban morphology and ventilation conditions. Through 3D modeling and Computational Fluid Dynamics (CFD) simulation, we focus on the large scale ventilation of an extended area with several buildings. As a testbed, in particular, the core part of Kwun Tong industrial park in Hong Kong is examined, and in order to validate the approach, 10 measurement points are used to get experimental values to More >

Qinghua Wang¹, Junzheng Yang¹, Wei Luo^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.1, pp. 215-233, 2021, DOI:10.32604/fdmp.2021.011914 - 09 February 2021

Abstract Well completions are generally used to connect a reservoir to the surface so that fluids can be produced from or injected into it. With these systems, pipe flows are typically established in the horizontal sections of slotted screen completions and inflow control device (ICD) completions; moreover, an annular flow exists in the region between the pipe and the borehole wall. On the basis of the principles of mass and momentum conservation, in the present study, a coupling model considering the variable mass flow of the central tubing, the variable mass flow of the annular tubing… More >

Yu Zhou^1,*, Shen Ji^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.1, pp. 189-200, 2021, DOI:10.32604/fdmp.2021.011744 - 09 February 2021

Abstract The outbreak of Corona Virus (COVID-19) has spread over a large number of countries. The virus is typically transported inside liquid droplets produced by human beings. As a result, doctors operating in the consulting rooms of hospitals are potentially exposed to high risk. Taking into account the evaporation of droplets and using a hybrid Eulerian-Lagrangian framework to determine the airflow pattern and corresponding motion of droplets, in the present study, the motion of droplets is investigated with regard to the situation in which doctors check patients in front of their bed. A turbulence model (RNG k-ɛ) More >

Mengyuan Cao, Yi Xu^*, Yilin Dong

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.1, pp. 123-139, 2021, DOI:10.32604/fdmp.2021.011443 - 09 February 2021

Abstract The damage caused by thermal stress during rewarming vitrified biosamples is one of the major obstacles for clinical purposes. Magnetic warming is a highly effective approach to overcome this hurdle and can achieve rapid and spatially homogeneous heating. The current research investigates the effects of magnetic warming on the histological and biomechanical properties of the vitrified umbilical arteries (UAs) through experiments and simulation. The results of experiments show that, for the case of magnetic warming comparing with the conventional water bath, magnetic warming presents better preservation of extracellular matrix (ECM), collagen fibers, elastic fibers, and… 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 - 09 February 2021

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 More >