Guanpeng Li¹, Lihui Sun², Zhaoyang Wang¹, Chunguo An¹, Chang Guo^3,*, Shen Cheng³, Ming Gao^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.5, pp. 989-1001, 2021, DOI:10.32604/fdmp.2021.016507 - 05 July 2021

Abstract Centrifugal pumps are widely used in engineering for a variety of applications. A known drawback of these devices is the high-level noise generated during operations, which can affect their stability and adversely influence the entire working environment. By combining the Powell vortex sound theory, numerical simulations and experimental measurements, this research explores the trends of variation and the corresponding underlying mechanisms for the flow-induced noise at various locations and under different operating conditions. It is shown that the total sound source intensity (TSSI) and total sound pressure level (TSPL) in the impeller, in the region More >

Qingzhuo Chi¹, Huimin Chen¹, Lizhong Mu^1,*, Ying He¹, Yong Luan²

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.4, pp. 721-743, 2021, DOI:10.32604/fdmp.2021.015200 - 17 May 2021

Abstract Type A aortic dissection (AD) is one of the most serious cardiovascular diseases, whose risk predictors are controversial. The purpose of this research was to investigate how elongation accompanied by dilation of the ascending aorta (AAo) affects the relevant haemodynamic characteristics using image-based computational models. Five elongated AAos with different levels of dilation have been reconstructed based on the centerlines data of an elderly and an AD patient. Numerical simulations have been performed assuming an inflow waveform and a Windkessel model with three elements for all outflow boundaries. The numerical results have revealed that the More >

Jianxin Hu, Xin Huang, Yuzhen Jin^*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.3, pp. 597-614, 2021, DOI:10.32604/fdmp.2021.014249 - 29 April 2021

Abstract By studying the characteristics of the flow field around a swimming fish, useful insights can be obtained into the superior swimming capabilities developed by nature over millions of years, in comparison to what can be achieved using the standard engineering principles traditionally employed in naval and ocean engineering. In the present study, the flow field related to a single joint fish model is simulated in the framework of a commercial computational fluid dynamics software (ANSYS Fluent 18.0). The principle of the anti-Kármán vortex street is analyzed and the relationship between the direction of the tail More >

Li-an Zhao^1,*, Tieli Wang²

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.2, pp. 413-426, 2021, DOI:10.32604/fdmp.2021.011205 - 02 April 2021

Abstract The transportation in vertical pipelines of particle slurry of oil shale has important applications in several fields (marine mining, hydraulic mining, dredging of river reservoir, etc.). However, there is still a lack of information about the behavior of coarse particles in comparison to that of fine particles. For this reason, experiments on the fluidization and hydraulic lifting of coarse oil shale particles have been carried out. The experimental data for three kinds of particles with an average size of 5 mm, 15 mm and 25 mm clearly demonstrate that vortices can be formed behind the… More >

Rachid Maouedj¹, Younes Menni², Mustafa Inc^3,4,*, Yu-Ming Chu^5,6,*, Houari Ameur⁷, Giulio Lorenzini⁸

CMES-Computer Modeling in Engineering & Sciences, Vol.126, No.3, pp. 855-889, 2021, DOI:10.32604/cmes.2021.014524 - 19 February 2021

Abstract Re-engineering the channel heat exchangers (CHEs) is the goal of many recent studies, due to their great importance in the scope of energy transport in various industrial and environmental fields. Changing the internal geometry of the CHEs by using extended surfaces, i.e., VGs (vortex generators), is the most common technique to enhance the efficiency of heat exchangers. This work aims to develop a new design of solar collectors to improve the overall energy efficiency. The study presents a new channel design by introducing VGs. The FVM (finite volume method) was adopted as a numerical technique… More >

Mohamed Salmi^1,2, Younes Menni³, Ali J. Chamkha^4,5,*, Houari Ameur⁶, Rachid Maouedj⁷, Ahmed Youcef⁷

CMES-Computer Modeling in Engineering & Sciences, Vol.126, No.1, pp. 147-173, 2021, DOI:10.32604/cmes.2021.012839 - 22 December 2020

Abstract The hydrothermal behavior of air inside a solar channel heat exchanger equipped with various shaped ribs is analyzed numerically. The bottom wall of the exchanger is kept adiabatic, while a constant value of the temperature is set at the upper wall. The duct is equipped with a flat rectangular fin on the upper wall and an upstream V-shaped baffle on the lower wall. Furthermore, five hot wall-attached rib shapes are considered: trapezoidal, square, triangular pointing upstream (type I), triangular pointing downstream (type II), and equilateral-triangular (type III) cross sections. Effects of the flow rates are… More >

Ioannis Oxyzoglou^*, Zheng-Tong Xie

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.6, pp. 1093-1114, 2020, DOI:10.32604/fdmp.2020.012237 - 17 December 2020

Abstract The broad implication of the paper is to elucidate the significance of the dynamic heaving motion in the aerodynamic performance of multi-element wings, currently considered as a promising aspect for the improvement of the aerodynamic correlation between CFD, wind tunnel and track testing in race car applications. The relationship between the varying aerodynamic forces, the vortex shedding, and the unsteady pressure field of a heaving double-element wing is investigated for a range of mean ride heights, frequencies, and amplitudes, using a two-dimensional (2D) unsteady Reynolds-averaged Navier-Stokes (URANS) approach and an overset mesh method for modelling… 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 >

Yong Guan¹, Wanling Hu^{1, 2, *}, Yun Zhang¹, Kewei Song^{2, 3}, Liangbi Wang^{2, 3}

CMES-Computer Modeling in Engineering & Sciences, Vol.123, No.1, pp. 237-256, 2020, DOI:10.32604/cmes.2020.09141 - 01 April 2020

Abstract The application of vortex generators in tube-finned heat exchangers is very universal. The vortex generators can generate secondary flow, and as we all know secondary flow can obviously strengthen heat transfer. To use vortex generators much more efficiently in the circle tube-finned heat exchangers, the intensity correlation study between secondary flow and heat transfer is needed. 22 different structures of circle tubefinned heat exchangers were numerically studied, including the plain fin cases and the cases with vortex generators. In addition, the influence of fin spacing, transverse and longitudinal tube pitch, heights and attack angle of More >

Tin-Kan Hung^1,*, Ruei-Hung Kuo², Cheng-Hsien Chiang³

Molecular & Cellular Biomechanics, Vol.17, No.1, pp. 19-24, 2020, DOI:10.32604/mcb.2019.07817

Abstract Kinematic and dynamic characteristics of pulsating flow in a model of human aortic arch are obtained by a computational analysis. Three-dimensional flow processes are summarized by pressure distributions on the symmetric plane together with velocity and pressure contours on a few cross sections for systolic acceleration and deceleration. Without considering the effects of aortic tapering and the carotid arteries, the development of tubular boundary layer with centrifugal forces and pulsation are also analyzed for flow separation and backflow during systolic deceleration. More >