Zechen Yao¹, Renfeng Yang^1,*, Haichao An²

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.2, pp. 397-412, 2021, DOI:10.32604/fdmp.2021.012114

Abstract Computational fluid dynamics (CFD) has been used to analyze the mixing process of Asphalt and Rubber (AR) in a stirred tank with a six flat-blade disc turbine (Rushton), a down-pumping 45° pitched-blade turbine (PBTD-6) and a down-pumping propeller (TXL). The two-phase (solid-liquid) flow in the considered stirred tank has been modelled in the framework of an Eulerian-Eulerian approach, a laminar-flow assumption and a multi-reference frame strategy. The following effects have been investigated: The influence of the impeller speed, impeller type, crumb rubber (CR) particle diameter and initial CR particle loading on the quality of the CR particle’s suspension. The outcomes… More >

Neil Stephen Lopez^1,*, Selena Kay Galeos¹, Brian Raphael Calderon¹, David Roy Dominguez¹, Bryan Joseph Uy¹, Rupesh Iyengar²

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.2, pp. 333-347, 2021, DOI:10.32604/fdmp.2021.011213

Abstract The underfloor air distribution (UFAD) system has not been able to penetrate the residential and commercial air conditioning industry significantly until now. To date, the most notable applications are found in datacenters because of their more demanding thermal stratification and cooling requirements. In addition to highlighting the advantages of the UFAD system over the traditional overhead (OH) system, this study compares various ventilation layouts for a UFAD system. Four different UFAD ventilation layouts are compared and one OH layout. The results show that using multiple swirl-type diffusers creates a more uniform floor-to-knee temperature and less air recirculation than the rectangular… More >

Makoto Yamamoto^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.23, No.1, pp. 19-19, 2021, DOI:10.32604/icces.2021.08478

Abstract In a turbine of a jet engine, deposition phenomenon is often observed. Deposition is a phenomenon that particles such as volcanic ash, sand and dust passing through a combustion chamber of a jet engine are melt, rapidly cooled and then accumulate on the turbine blade and end-wall surfaces. Deposition is one of critical problems when aircraft flies in a cloud with many particles. Obviously, deposition can degrade the aerodynamic performance of the turbine blade and vane, and make partial or complete blockage of film-cooling holes. As the result, deposition deteriorates safety and life time of the turbine. In the past… 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

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 to solve the problem, with… 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

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 adequately inhibits leakage flow.… 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

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 be used for comparison (such… More >

Mohamad Shukri Zakaria^1,*, Haslina Abdullah², Azmi Nordin¹, Syazwati Ahmad Zaki¹

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.1, pp. 171-179, 2021, DOI:10.32604/fdmp.2021.010974

Abstract This study deals with the interaction of blood flow with the wall aorta, i.e., the boundary of the main artery that transports blood in the human body. The problem is addressed in the framework of computational fluid dynamics complemented with (FSI), i.e., a fluid-structure interaction model. Two fundamental types of wall are considered, namely a flexible and a rigid boundary. The resulting hemodynamic flows are carefully compared in order to determine which boundary condition is more effective in reproducing reality. Special attention is paid to wall shear stress (WSS), a factor known for its ability to produce atherosclerosis and bulges.… More >

Sheng Bai, Feng Bao^*, Fengzhi Zhao

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.1, pp. 39-47, 2021, DOI:10.32604/fdmp.2021.010376

Abstract The present study aims to improve the efficiency of typical procedures used for post-processing flow field data by applying a neural-network technology. Assuming a problem of aircraft design as the workhorse, a regression calculation model for processing the flow data of a FCN-VGG19 aircraft is elaborated based on VGGNet (Visual Geometry Group Net) and FCN (Fully Convolutional Network) techniques. As shown by the results, the model displays a strong fitting ability, and there is almost no over-fitting in training. Moreover, the model has good accuracy and convergence. For different input data and different grids, the model basically achieves convergence, showing… 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

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 also inspected for various Reynolds… 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

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 the moving wing. The analysis… More >