Xiao Sun¹, Huifan Huang¹, Yuliang Zhang², Lianghuai Tong^3,*, Xiaowei Xu², Xiaoqi Jia⁴, Litao Ou⁵

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.10, pp. 2251-2264, 2024, DOI:10.32604/fdmp.2024.050997 - 23 September 2024

Abstract In order to obtain the transient characteristics of a low-speed centrifugal pump during the start-up and shutdown stages, dedicated experimental tests were conducted with eight different valve opening conditions. The Pearson correlation coefficient was used to reveal the linear correlation between variables. According to the results, the stable rotational speed decreases with increasing valve opening (rotational speed decreases from approximately 1472 to 1453 r/min), while the stable shaft power exhibits an increasing trend (shaft power increases from approximately 0.242 to 0.390 kW). The stable time and zeroing time of each parameter during start-up and shutdown 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 - 16 May 2023

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 More > Graphic Abstract

Huanwei Xu^*, Wenzhang Wei, Hanjin He, Xuerui Yang

CMES-Computer Modeling in Engineering & Sciences, Vol.132, No.1, pp. 173-199, 2022, DOI:10.32604/cmes.2022.019424 - 02 June 2022

Abstract The surrogate model technology has a good performance in solving black-box optimization problems, which is widely used in multi-domain engineering optimization problems. The adaptive surrogate model is the mainstream research direction of surrogate model technology, which can realize model fitting and global optimization of engineering problems by infilling criteria. Based on the idea of the adaptive surrogate model, this paper proposes an efficient global optimization algorithm based on the local remodeling method (EGO-LR), which aims at improving the accuracy and optimization efficiency of the model. The proposed algorithm firstly constructs the expectation improvement (EI) function… More >

Ting Zhang¹, Denghao Wu^1,2,*, Shijun Qiu², Peijian Zhou¹, Yun Ren³, Jiegang Mou¹

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.5, pp. 1349-1361, 2022, DOI:10.32604/fdmp.2022.019617 - 27 May 2022

Abstract Stall phenomena increase the complexity of the internal flow in centrifugal pump impellers. In order to tackle this problem, in the present work, a large eddy simulation (LES) approach is applied to determine the characteristics of these unstable flows. Moreover, a vorticity identification method is used to characterize quantitatively the vortex position inside the impeller and its influencing area. By comparing the outcomes of the numerical simulations and experimental results provided by a Particle Image Velocimetry (PIV) technique, it is shown that an apparent “alternating stall” phenomenon exists inside the impeller when relatively small flow More >

Xiaorui Cheng^1,2,*, Xiang Liu¹, Boru Lv¹

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.1, pp. 93-107, 2022, DOI:10.32604/fdmp.2022.017566 - 10 November 2021

Abstract An AP1000 nuclear reactor coolant pump is considered to assess the influence of the Impeller/Guide vane clearance on the performances of this type of pumps. Experiments and numerical simulations relying on an unidirectional fluid-solid coupling approach are used to investigate the problem (stress, strain and mode of the rotor). The results reveal the relationship existing between the hydraulic performance of the nuclear reactor coolant pump and the clearance ratio. The effect of clearance ratio on the maximum equivalent stress on the back surface of the impeller blade is greater than that on the working surface More >

Ravindra Birajdar^1,*, Appasaheb Keste², Shravan Gawande²

Sound & Vibration, Vol.55, No.4, pp. 305-327, 2021, DOI:10.32604/sv.2021.017000 - 18 October 2021

Abstract The objective of the study is to find the tolerance on vane pitch dimensions of a Vertical Turbine (VT) pump impeller. For this purpose, the study is divided into two parts viz. to find the critical hydraulic eccentricity of a VT pump impeller by way of numerical simulations and design of experiments to find the vane pitch tolerance using critical hydraulic eccentricity. The effect of impeller vane pitch deviations on hydraulic unbalance is examined for a vertical turbine pump using Design of Experiments (DOE). A suitable orthogonal matrix has been selected with vane pitch at More >

Jinguang Yang, Feng Zhao, Min Zhang^*, Yan Liu, Xiaofang Wang

CMES-Computer Modeling in Engineering & Sciences, Vol.126, No.3, pp. 935-953, 2021, DOI:10.32604/cmes.2021.014176 - 19 February 2021

Abstract For a radial inflow turbine (RIT), leakage flow in impeller backface cavity has critical impacts on aerodynamic performance of the RIT and axial force acting on the RIT impeller. In order to control this leakage flow, different types of labyrinth seals are numerically studied in this paper based on a supercritical carbon dioxide (S-CO₂) RIT. The effects of seal clearance and cavity outlet pressure are first analyzed, and the impacts of seal design parameters, including height, number and shape of seal teeth, are evaluated. Results indicate that adding labyrinth seal can improve cavity pressure and hence More >

Weimin Wu, Chuande Zhou^*

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.5, pp. 883-901, 2020, DOI:10.32604/fdmp.2020.010407 - 09 October 2020

Abstract The behavior of the tip wake of a wind turbine is one of the hot issues in the wind power field. This problem can partially be tackled using Computational Fluid Dynamics (CFD). However, this approach lacks the ability to provide insights into the spatial structure of important high-order flows. Therefore, with the horizontal axis wind turbine as the main focus, in this work, firstly, we conduct CFD simulations of the wind turbine in order to obtain a data-driven basis relating to multiple working conditions for further analysis. Then, these data are studied using an extended More >

Peng Tian¹, Jun Huang¹, Weidong Shi^1,2,*, Ling Zhou¹

FDMP-Fluid Dynamics & Materials Processing, Vol.15, No.2, pp. 139-151, 2019, DOI:10.32604/fdmp.2019.05216

Abstract A prototype centrifugal pump with a specific speed of 110 is used to investigate and optimize the performances of a turbine for power generation. Particular attention is given to the design of the internal impeller. The internal flow field is simulated in the framework of a commercial computational fluid dynamics software (ANSYS). Four geometrical parameters of the impeller are considered, i.e., the inlet diameter, the inlet width, the blade number, and the blade angle. The optimization is carried out on the basis of a three-level approach relying on an orthogonal test method. The results of More >

K. Kakuda¹, T. Nagashima¹, Y. Hayashi¹, S. Obara¹, J. Toyotani¹, S. Miura², N. Katsurada³, S. Higuchi³, S. Matsuda³

CMES-Computer Modeling in Engineering & Sciences, Vol.93, No.5, pp. 363-376, 2013, DOI:10.3970/cmes.2013.093.363

Abstract The application of a GPU-based particle method to three-dimensional incompressible viscous fluid flow problems is presented. The particle approach is based on the MPS (Moving Particle Semi-implicit) scheme using logarithmic weighting function to stabilize the spurious oscillatory solutions for solving the Poisson equation with respect to the pressure fields by using GPU-based SCG (Scaled Conjugate Gradient) method. Numerical results demonstrate the workability and the validity of the present approach through the dam-breaking flow problem and flow behavior in a liquid ring pump with rotating impeller blades. More >