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 >

Sulardjaka Sulardjaka^1,*, Sri Nugroho¹, Norman Iskandar¹, Agus P. Adi¹, Deni F. Fitriyana²

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.2, pp. 385-395, 2021, DOI:10.32604/fdmp.2021.011784

Abstract Zeolite A has been successfully synthesized from geothermal waste with natrium aluminate and natrium silicate using conventional (C-H) and microwave heating (M-H) for the hydrothermal treatment. The products obtained for different aging times have been characterized using X-Ray Diffraction (XRD), Fourier transformation infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). It is shown that with the M-H process, zeolite can be formed at relatively low temperature (100°C) in a relatively short time (40 min). The crystallization of zeolite A has been found to be generally promoted by an increase of aging and synthesis time; however, it has also been observed… More >

Xinke Yang¹, Shanzhi Shi¹, Hui Zhang¹, Yuzhe Yang^2,3, Zilong Liu^2,3, Ruiquan Liao^2,3,*, Joseph X. F. Ribeiro⁴

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.2, pp. 371-383, 2021, DOI:10.32604/fdmp.2021.011486

Abstract The accurate prediction of the pressure distribution of highly viscous fluids in wellbores and pipelines is of great significance for heavy oil production and transportation. The flow behavior of high-viscosity fluids is quite different with respect to that of low-viscosity fluids. Currently, the performances of existing pressure-drop models seem to be relatively limited when they are applied to high-viscosity fluids. In this study, a gas-liquid two-phase flow experiment has been carried out using a 60 mm ID horizontal pipe with air and white oil. The experimental results indicate that viscosity exerts a significant influence on the liquid holdup and pressure… 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 >

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

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 particles. On this basis, a… More >

Ruixin Zhao^1,*, Zhongju Feng¹, Guan Jiang¹, Fuchun Wang¹, Yidong Zhang², Changan Zhang³, Zhenbing Wang¹

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.2, pp. 441-453, 2021, DOI:10.32604/fdmp.2021.010595

Abstract The present study examines the working conditions of fully grouted bolts used for the construction and expansion of high slopes. On the basis of a pull out destructive test, the work load and the ultimate load are obtained on site, and the Flac3d numerical simulation method is employed to determine the axial force distribution and the effective anchor length. The test results show that (1) the Q-S (load-displacement) curve of the bolt displays a certain degree of deformation coupled with the creep of the surrounding rock; (2) the working load of the bolt is closely related to the sliding deformation… More >

Zongkai Liu^1,2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.2, pp. 427-439, 2021, DOI:10.32604/fdmp.2021.010528

Abstract The so-called surface Magneto-hydro-dynamic (MHD) propulsion relies on the Lorentz force induced in weak electrolyte solutions (such as seawater or plasma) by NdFeB Magnets. The Lorentz force plays an important role in such dynamics as it directly affects the structures of flow boundary layers. Previous studies have mainly focused on the development of such boundary layers and related fluid-dynamic aspects. The main focus of the present study is the determination of electromagnetic field distributions around the propulsion units. In particular dedicated experiments and numerical simulations (based on the finite volume method) are conducted considering a NACA0012 airfoil immersed in seawater.… More >

Elio Caruso¹, Silvia Farruggio^1,*, Davide Calvaruso¹, Corrado Di Mambro¹, David Angel Ortiz Ruiz¹, Salvatore Agati¹, Rafie Khoargami²

Congenital Heart Disease, Vol.16, No.4, pp. 417-425, 2021, DOI:10.32604/CHD.2021.015808

Abstract We show a brief report of two common arterial trunk cases (CAT) with different arrhythmias and discuss anatomy, clinical and diagnostic management. The burden of volume and pressure overload of this cardiac malformation may predispose to different types of arrhythmia before and after surgical repair. Because of labile hemodynamic state in this group of patients, prompt diagnosis of any arrhythmia is mandatory as the devastating factor on prognosis. The first patient with a diagnosis of CAT Type II Collett and Edwards (CE) had a particular history with HIV seropositive mother assuming antiretroviral therapy during pregnancy, who presented hyperbilirubinemia and liver… More >

Yajuan Zhang, Jun Yan^*, Qiang Wang, Shoujun Li, Jing Sun, Shuo Dong, Jiachen Li

Congenital Heart Disease, Vol.16, No.4, pp. 383-392, 2021, DOI:10.32604/CHD.2021.015479

Abstract Background: The long-term outcomes of patients treated with a Kawashima procedure and keeping the antegrade pulmonary blood flow (AnPBF) in single-ventricle (SV) and interrupted inferior vena cava (IVC) heart disease is still uncertain as yet. Methods: We investigated 18 patients who underwent the Kawashima procedure with SV physiology and an interrupted IVC between January 2009 and June 2018, perioperative, operative and postoperative characteristics were recorded. Results: A total of 18 patients underwent the Kawashima procedure at a median age of 2.7 years (range 0.5–24.7 years), of which 12 (66.7%) were male and 6 (33.3%) were female. The mean saturation was… More >

Elio Caruso^*, Silvia Farruggio, Salvatore Agati, Corrado Di Mambro

Congenital Heart Disease, Vol.16, No.4, pp. 309-331, 2021, DOI:10.32604/CHD.2021.015470

Abstract Fetal arrhythmias reach up around 10% of the total third-level perinatal cardiology references. Sustained bradycardia is defined as a baseline fetal heart rate (FHR) of less than 110 bpm sustained for at least 10 min. The overall incidence of malignant fetal bradyarrhythmias, such as complete atrioventricular block (AVB) and channellopathies, is relatively rare, 1:5000 pregnancies, but represents a serious emergency for the gynecologist, neonatologists, and pediatric cardiologists. Fetal complete AVB is strongly associated with maternal connective tissue disease, but it can be also associated with congenital heart disease and usually with a poorer prognosis with high risk of fetal hydrops… More >