Jian Yao, Fayi Yan^*, Xuejian Pei

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1425-1445, 2023, DOI:10.32604/fdmp.2023.025282

Abstract Proton exchange membrane fuel cells (PEMFCs) are largely used in various applications because of their pollution-free products and high energy conversion efficiency. In order to improve the related design, in the present work a new spiral flow field with a bypass is proposed. The reaction gas enters the flow field in the central path and diffuses in two directions through the flow channel and the bypass. The bypasses are arranged incrementally. The number of bypasses and the cross-section size of the bypasses are varied parametrically while a single-cell model of the PEMFC is used. The influence of the concentration of… More > Graphic Abstract

Feiran Lv¹, Min Wang², Chuntian Zhe¹, Chang Guo³, Ming Gao^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.6, pp. 1463-1478, 2023, DOI:10.32604/fdmp.2023.024259

Abstract The so-called T-shaped reducing tees are typically used to divide, change and control (to a certain extent) the flow direction in pipe networks. In this study, the Ffowcs Williams–Hawkings (FW-H) equation and the Large Eddy Simulation (LES) methods are used to simulate the flow-induced noise related to T-shaped reducing tees under different inlet flow velocities and for different pipe diameter ratios. The results show that the maximum flow velocity, average flow velocity, and vorticity in the branch pipe increase gradually as the related diameter decreases. Strong vorticity and secondary flows are also observed in the branch pipe, and the associated… More > Graphic Abstract

Roudouane Laouar^1,*, Olaf Wünsch²

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.4, pp. 1055-1066, 2023, DOI:10.32604/fdmp.2022.022677

Abstract In this work, a parametric two-dimensional computational fluid dynamics (CFD) analysis of a solar chimney power plant (a prototype located in Manzanares, Spain) is presented to illustrate the effects of the solar radiation mode in the collector on the plant performances. The simulations rely on a mathematical model that includes solar radiation within the collector; energy storage; air flow and heat transfer, and a turbine. It is based on the Navier-Stokes equation for turbulent flow formulated according to the standard k-ε model. Moreover, the Boussinesq approach is used to account for the fluid density variations. Different solar radiation modes in… More >

Li Luo¹, Yuhang Fan¹, Yu Wang¹, Peiyong Ni¹, Xuewen Zhang¹, Guannan Xi^2,*

Energy Engineering, Vol.120, No.1, pp. 125-145, 2023, DOI:10.32604/ee.2022.022295

Abstract This paper aims to design a special exchanger to recover the exhaust gas heat of marine diesel engines used in small and medium-sized fishing vessels, which can then be used to heat water up to 55°C–85°C for membrane desalination devices to produce fresh water. A new exhaust-gas heat exchanger of fins and tube, with a reinforced heat transfer tube section, unequal spacing fins, a mixing zone between the fin groups and four routes tube bundle, was designed. Numerical simulations were also used to provide reference information for structural design. Experiments were carried out for exhaust gas waste heat recovery from… More >

Danqing Huang^*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.3, pp. 845-854, 2023, DOI:10.32604/fdmp.2022.020314

Abstract A two-dimensional mathematical model is used to simulate the influence of water flow on the piers of a bridge for different incidence angles. In particular, a finite volume method is used to discretize the Navier-Stokes control equations and calculate the circumferential pressure coefficient distribution on the bridge piers’ surface. The results show that the deflection of the flow is non-monotonic. It first increases and then decreases with an increase in the skew angle. More >

Wenbin Luo^1,*, Youmin Wang¹, Yuting Yan², Yifang Shi¹, Zhendong Zhang³

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.3, pp. 789-813, 2022, DOI:10.32604/fdmp.2022.019691

Abstract In order to determine the optimal structural parameters of a plastic centrifugal pump in the framework of an orthogonal-experiment approach, a numerical study of the related flow field has been performed using CFX. The thickness S, outlet angle β2, inlet angle β1, wrap angle, and inlet diameter D1 of the splitter blades have been considered as the variable factors, using the shaft power and efficiency of the pump as evaluation indices. Through a parametric analysis, the relative importance of the influence of each structural parameter on each evaluation index has been obtained, leading to the following combinations: β1 19°, β2… More >

Bing Liu¹, Yikun Chen¹, Huachen Liu¹, Qiao Wu¹, Minghui Wang¹, Jianlong Wan^2,*

Energy Engineering, Vol.119, No.2, pp. 815-826, 2022, DOI:10.32604/ee.2022.017988

Abstract The operating range of the flow rate or flow velocity for the micro-jet flame is quite wide, which can be used as the heat source. In order to optimize the micro-jet tube combustor in terms of the solid material, the present paper numerically investigates the impact of thermal conductivity (λ_s) on the operating limit of micro-jet flame. Unexpectedly, the non-monotonic blow-off limits with the increase of λ_s is found, and the corresponding generation mechanisms are analyzed in terms of the thermal coupling effect, flow field, and strain effect. At first, the lower preheating temperature of the fuel and larger heat… More >

Deng Qin¹, Tian Li^1,*, Honglin Wang², Jizhong Yang³, Yao Jiang³, Jiye Zhang¹, Haiquan Bi²

CMES-Computer Modeling in Engineering & Sciences, Vol.130, No.3, pp. 1371-1386, 2022, DOI:10.32604/cmes.2022.018480

Abstract The aerodynamic noise of high-speed trains passing through a tunnel has gradually become an important issue. Numerical approaches for predicting the aerodynamic noise sources of high-speed trains running in tunnels are the key to alleviating aerodynamic noise issues. In this paper, two typical numerical methods are used to calculate the aerodynamic noise of high-speed trains. These are the static method combined with non-reflective boundary conditions and the dynamic mesh method combined with adaptive mesh. The fluctuating pressure, flow field and aerodynamic noise source are numerically simulated using the above methods. The results show that the fluctuating pressure, flow field structure… More >

M. Narendra Kumar^1,*, S. Manoj Kumar², G. C. Vijayakumar¹, K. Kadirgama^3,4, M. Samykano⁵, Krishna Venkatesh¹, H. B. Murlidhara¹

Energy Engineering, Vol.119, No.1, pp. 201-217, 2022, DOI:10.32604/EE.2022.016597

Abstract This study computationally investigates the hydrodynamics of different serpentine flow field designs for redox flow batteries, which considers the Poiseuille flow in the flow channel and the Darcy flow porous substrate. Computational Fluid Dynamics (CFD) results of the in-house developed code based on Finite Volume Method (FVM) for conventional serpentine flow field (CSFF) agreed well with those obtained via experiment. The deviation for pressure drop was less than 5.1% for all the flow rates, thus proving the present CFD analysis’s validity on the modified variation of serpentine flow fields. Modified serpentine flow field-2 (MSFF2) design provided least pressure drop across… More >

Quanbin Ba^1,2, Yanbao Liu^1,2,*, Zhigang Zhang^1,2, Wei Xiong^1,2, Kai Shen^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.4, pp. 697-710, 2021, DOI:10.32604/fdmp.2021.014762

Abstract The characteristics of the flow field associated with a multi-hole combined external rotary bit have been studied by means of numerical simulation in the framework of an RNG k-ε turbulence model, and compared with the results of dedicated rock breaking drilling experiments. The numerical results show that the nozzle velocity and dynamic pressure of the nozzle decrease with an increase in the jet distance, and the axial velocity of the nozzle decays regularly with an increase in the dimensionless jet distance. Moreover, the axial velocity related to the nozzle with inclination angle 20° and 30° can produce a higher hole… More >