Junying Wei^*, Gang Li, Chenrui Zhang, Wenwen Chang, Jidai Wang

Frontiers in Heat and Mass Transfer, Vol.21, pp. 199-214, 2023, DOI:10.32604/fhmt.2023.041793

Abstract To study the complex internal flow field variation and output characteristics of a variable base radius scroll expander, this paper uses dynamic mesh techniques and computational fluid dynamics (CFD) methods to perform transient numerical simulations of a variable base radius scroll expander. Analysis of the flow field in the working cavity of a variable base radius scroll expander at different spindle angles and the effect of different profiles, speeds and pressures on the output characteristics of the scroll expander. The results of the study show that due to the periodic blocking of the inlet by the orbiting scroll, the fluid… More >

Yue Cui^1,*, Liyuan Wang², Jian Wu¹, Haisheng Liu¹, Di Wu¹

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.1, pp. 165-177, 2024, DOI:10.32604/fdmp.2023.030311

Abstract This study aims to improve the performances of the high-pressure water descaling technology used in steel hot rolling processes. In particular, a 2050 mm hot rolling line is considered, and the problem is investigated by means of a fluid–structure interaction (FSI) method by which the descaling effect produced by rolling coils with different section sizes is examined. Assuming a flat fan-shaped nozzle at the entrance of the R1R2 roughing mill, the out- flow field characteristics and the velocity distribution curve on the strike line (at a target distance of 30–120 mm) are determined. It is found that the velocity in… More >

Yongxin Liu¹, Huaiwei Cao², Puyu Zhao², Gang Yang¹, Hua Yu¹, Fuwei He³, Bo He^2,*

Energy Engineering, Vol.120, No.10, pp. 2417-2431, 2023, DOI:10.32604/ee.2023.029596

Abstract When using high-voltage transmission lines for energy transmission in loess hilly regions, local extreme wind fields such as turbulence and high-speed cyclones occur from time to time, which can cause many kinds of mechanical and electrical failures, seriously affecting the reliable and stable energy transmission of the power grid. The existing research focuses on the wind field simulation of ideal micro-terrain and actual terrain with mostly single micro-terrain characteristics. Model boundary constraints and the influence of constrained boundaries are the main problems that need to be solved to accurately model and simulate complex flow fields. In this paper, a flow… More >

Dongxiao Zhang¹, Lin Lu^1,*, Xiaobin Qi^2,3, Xuepu Yan¹, Cisong Gao¹, Yanxiao Hu¹

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.10, pp. 2707-2728, 2023, DOI:10.32604/fdmp.2023.028641

Abstract A two-dimensional model, employing a dynamic mesh technology, is used to simulate numerically the transient multiphase flow field produced by two submerged parallel guns. After a grid refinement study ensuring grid independence, five different conditions are considered to assess the evolution of cavitation occurring in proximity to the gun muzzle. The simulation results show that flow interference is enabled when the distance between the parallel barrels is relatively small; accordingly, the generation and evolution of the vapor cavity becomes more complex. By means of the Q criterion for vorticity detection, it is shown that cavitation causes the generation of vorticity… More >

Yuqin Wang^1,2,3,*, Luxiang Zhou³, Mengle Han¹, Lixiang Shen¹

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.9, pp. 2215-2228, 2023, DOI:10.32604/fdmp.2023.027188

Abstract The main structural parameters of the IR100-80-100A type chemical centrifugal pump have been optimized by means of an orthogonal test approach. The centrifugal pump has been modeled using the CFturbo software, and 16 sets of orthogonal-test schemes have been defined on the basis of 4 parameters, namely, the blade number, blade outlet angle, impeller outlet diameter, and impeller outlet width. Such analysis has been used to determine the influence of each index parameter on the pump working efficiency and identify a set of optimal combinations of such parameters. The internal flow field in the centrifugal pump has been simulated by… More > Graphic Abstract

O. M. Oyewola^a,b,*, O. S. Ismail^b, J. O. Bosomo^b

Frontiers in Heat and Mass Transfer, Vol.17, pp. 1-5, 2021, DOI:10.5098/hmt.17.8

Abstract This paper investigates possible inherent modifications of the radiative heat source term due to the influence of turbulence in the thermal radiation field of a gas turbine combustor flame. Adapting a flame temperature of 2000[K], COMSOL Multiphysics software was utilized to numerically simulate the process, assuming a gray gas participating medium with absorption coefficient of 0.03[m^-1]. The analysis of the results for five (5) different radial cut sections of the simulated combustor chamber shows that turbulence-radiation interactions cause radiative heat losses from the flame, with the divergence of the radiative heat flux having a deviation factor of 3.48, and a… More >

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 >