scholarly journals Quantitative characterization of volume of cavities in hydrodynamic cavitation device using computational fluid dynamics

2020 ◽  
Vol 24 ◽  
pp. e28
Author(s):  
Thiago Vinicius Ribeiro Soeira ◽  
Guilherme Barbosa Lopes Junior ◽  
Cristiano Poleto ◽  
Julio Cesar de Souza Inácio Gonçalves
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Experimental Studies ◽  
Hydrodynamic Cavitation ◽  
Quantitative Characterization ◽  
Flow Parameters ◽  
Cavitation Intensity ◽  
Computational Fluid Dynamics Cfd ◽  
Diffuser Angle

Hydrodynamic cavitation has been extensively studied for its potential to remove emerging pollutants. Despite the advance of the experimental studies involving this phenomenon, computational studies that evaluate the influence of the geometry of the cavitation devices on the flow parameters are still necessary. The purpose of this article was to evaluate the influence of the change in the geometry of a Venturi device on the volume of cavities formed in its divergent section using Computational Fluid Dynamics (CFD). The geometric parameters modified in the Venturi were: the diffuser angle and the relation between the height and the width of the throat (h/w). The volume of cavities is an important parameter because it influences the cavitation intensity. A cavitational bench system was constructed in order to obtain input data for simulation. The results showed that the increase in the diffuser angle from 6.5° to 18.5° gradually reduced the volume of cavities from 93 mm3 to 10 mm3. Between the relations h/w = 0.05 and h/w = 0.45 was observed the formation of cavities between 106 mm3 and 77 mm3, however between h/w = 0.45 and h/w = 1.0 there was the formation of 213 mm3. Therefore, Venturi’s with diffuser angle less than 6.5º and relation h/w greater than 0.45 produce greater volume of cavities. The greater volume of cavities will not necessarily produce greater cavitational intensity, since cavitation clouds can be formed and reduce the implosion intensity of the cavitation bubbles.

scholarly journals DESIGN AND ANALYSIS OF AN AERODYNAMIC DOWNFORCE PACKAGE FOR A FORMULA STUDENT RACE CAR

2017 ◽  
Vol 18 (2) ◽  
pp. 212-224
Author(s):  
Muhammad Abid ◽  
Hafiz Abdul Wajid ◽  
Muhammad Zohair Iqbal ◽  
Shayan Najam ◽  
Ali Arshad ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Wind Tunnel ◽  
Experimental Studies ◽  
Numerical Results ◽  
Experimental Results ◽  
Race Car ◽  
Rear Wing ◽  
Computational Fluid Dynamics Cfd ◽  
Front Wing

This paper presents design of aerodynamic downforce generating devices (front wing, rear wing and diffuser) to enhance the performance of the Formula Student Race Car using numerical and experimental studies. Numerical results using computational fluid dynamics (CFD) studies were primarily validated with the experimental results performed in the wind tunnel. It was concluded that the use of a downforce package can enhance the performance of the vehicle in the competition.

Characterization of Single-Phase Flow Hydrodynamics in Berty Reactor using Computational Fluid Dynamics (CFD)

2021 ◽  
Author(s):  
Khunnawat Ountaksinkul ◽  
Sirada Sripinun ◽  
Panut Bumphenkiattikul ◽  
Surapon Bubphacharoen ◽  
Arthit Vongachariya ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Single Phase ◽  
Three Dimensional ◽  
Flow Characteristics ◽  
Kinetic Studies ◽  
Stirred Tank Reactors ◽  
Computational Fluid Dynamics Cfd ◽  
Continuous Stirred Tank

This work studies the flow characteristics in the Berty reactor, a gradientless reactor for kinetic studies, using three-dimensional (3D) computational fluid dynamics (CFD), and the non-ideal continuous stirred tank reactors...

Use of Computational Fluid Dynamics for the Replication of Clinical Blood Flow and Pressure Measurements and Characterization of Hemodynamics in the Normal Ascending and Thoracic Aorta

2007 ◽  
Author(s):  
John F. LaDisa ◽  
C. Alberto Figueroa ◽  
Irene E. Vignon-Clementel ◽  
Frandics P. Chan ◽  
Jeffrey A. Feinstein ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Blood Flow ◽  
Boundary Conditions ◽  
Thoracic Aorta ◽  
Vascular Anatomy ◽  
Data Set ◽  
Cfd Models ◽  
Computational Fluid Dynamics Cfd

Complications associated with abnormalities of the ascending and thoracic aorta are directly influenced by mechanical forces. To understand hemodynamic alterations associated with diseases in this region, however, we must first characterize related indices during normal conditions. Computational fluid dynamics (CFD) models of the ascending and thoracic aorta to date have only provided descriptions of the velocity field using idealized representations of the vasculature, a single patient data set, and outlet boundary conditions that do not replicate physiologic blood flow and pressure. Importantly, the complexity of aortic flow patterns, limited availability of methods for implementing appropriate boundary conditions, and ability to replicate vascular anatomy all contribute to the difficulty of the problem and, likely, the scarcity of more detailed studies.

Numerical Flow Analysis of Hydrate Formation in Offshore Pipelines Using Computational Fluid Dynamics (CFD)

2016 ◽  
Author(s):  
Eugenio Turco Neto ◽  
M. A. Rahman ◽  
Syed Imtiaz ◽  
Salim Ahmed
Keyword(s):  
Fluid Dynamics ◽  
Mass Transfer ◽  
Computational Fluid Dynamics ◽  
Reaction Kinetics ◽  
Formation Process ◽  
Formation Rate ◽  
Experimental Studies ◽  
Hydrate Formation ◽  
Computational Fluid Dynamics Cfd ◽  
Hydrate Formation Process

Hydrate formation is one of the major challenges faced by the Oil and Gas industry in offshore facilities due to its potential to plug wells and reduce production. Several experimental studies have been published so far in order to understand the mechanisms that govern the hydrate formation process under its thermodynamic favorable conditions; however, the results are not very accurate due to the uncertainties related to measurements and metastable behavior observed in some cases involving hydrate formation. Moreover, thermodynamic models have been proposed to overcome the latter constraints but they are formulated assuming thermodynamic equilibrium, which such condition is difficult to be achieved in flow systems due to the turbulence effects. Due to the low solubility of methane in water, the mass transfer effects can possibly control several mechanisms that are still unknown about the hydrate formation process. Also, the reaction kinetics plays a major rule in minimizing hydrate formation rate. The objective of this work is to develop a mechanistic Computational Fluid Dynamics (CFD) model in order to predict the formation of hydrate particles along the pipeline from a hydrate-free gas dominated stream constituted by methane and water only. The transient simulations were performed using a commercial CFD software package considering the multiphase hydrate chemical reaction and mass transfer resistances. The geometry used was a straight pipe with 5 m length and 0.0254 m diameter. The results have shown the appearance of regions in the pipeline at which hydrate formation is controlled either by the mass transfer or reaction kinetics. The rate of hydrate formation profile has shown to be high at the inlet even though the temperature at that regions was high, which can be a possible explanation for metastable region encountered in most of recent phase diagrams.

scholarly journals Characterization of Convective Transfer of Heat by Air Impingement using Single Swirling Jet with Insertion of Twisted Tapes by Computational Fluid Dynamics

2020 ◽  
Vol 9 (3) ◽  
pp. 35-38
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Heated Surface ◽  
Target Surface ◽  
Reynolds Numbers ◽  
Twisted Tape ◽  
Twisted Tapes ◽  
Air Impingement ◽  
Computational Fluid Dynamics Cfd

This study showed the analysis of heat transfer by computational fluid dynamics (CFD) from a heated target surface by the use of jet of single swirl and impingement by air at various Reynolds numbers. The half-length downstream with insertion of twisted tape is applied in a nozzle body to get the swirl. The distance between twist ratio and nozzle to plate of twisted tape is found to be same as y = 2.93 and 21mm (H/D = 1). The characteristics of transfer of heat on heated surface are determined with varied Reynolds numbers like 12000, 17000, 22000 and 27000.

Characterization of a Multiple-Channel Electrochemical Cell by Computational Fluid Dynamics (CFD) and Residence Time Distribution (RTD)

2019 ◽  
Vol 29 (1) ◽  
pp. 215-223 ◽  
Author(s):  
Armando I. Vázquez ◽  
Francisco J. Almazán ◽  
Martín Cruz-Diaz ◽  
José A. Delgadillo ◽  
María I. Lázaro ◽  
...  
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Residence Time ◽  
Time Distribution ◽  
Residence Time Distribution ◽  
Electrochemical Cell ◽  
Multiple Channel ◽  
Computational Fluid Dynamics Cfd

scholarly journals Nebulization Criteria and Quantification

Fluids ◽  
2020 ◽  
Vol 5 (2) ◽  
pp. 91
Author(s):  
Nardos Hailu ◽  
Michiel Postema ◽  
Ondrej Krejcar ◽  
Dawit Assefa
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Numerical Modeling ◽  
Health Sciences ◽  
Experimental Techniques ◽  
Environmental Sciences ◽  
Atmospheric Physics ◽  
Scientific Disciplines ◽  
Computational Fluid Dynamics Cfd

The application of atomization technology is common in fields such as agriculture, cosmetics, environmental sciences, and medicine. Aerosolized drugs are administered using nebulizers to treat both pulmonary and nonpulmonary diseases. The characterization and measurement of nebulizers are of great significance in analyzing the performance and accuracy of the nebulizing system and the advancement of the technology. Nevertheless, the characterization of aerosols has been a long-standing challenge in scientific disciplines ranging from atmospheric physics to health sciences. The study of factors that influence nebulization has not been undertaken systematically using experimental techniques. Numerical modeling (NM) and computational fluid dynamics (CFD) can address such issues. This article provides a concise overview of the literature on the application of computational fluid dynamics to medical nebulizers and aerosol measurements.

Computational Fluid Dynamics Applicable to Cloth Design

2009 ◽  
Author(s):  
Ana M. F. Cunha ◽  
Jose´ C. F. Teixeira ◽  
Senhorinha F. C. F. Teixeira
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Human Body ◽  
Thermal Manikin ◽  
Clothing Insulation ◽  
Mass Transfer Processes ◽  
Different Temperatures ◽  
Computational Fluid Dynamics Cfd ◽  
Combined Simulation

Increasingly, different concepts such as safety, hygiene and comfort interact in the characterization of the workplaces. Being comfortable during periods of low activity, seems to be a requirement for most people and, secondly, in other sectors where performance is critical, the priorities are different. In both cases, the intellectual and physical performance is strongly affected by the sensation of thermal comfort. Thus, various approaches can be applied to provide comfort, for example, in the design of buildings and the selection of appropriate clothing. Comfortable clothing is a complex and interdisciplinary concept, consisting of a balance of the sensorial, psychological and physiological aspects [1, 2]. In objective terms, the behavior of the human body depends on several factors: temperature, air velocity and humidity, production of metabolic heat and clothing insulation. All these factors determine the heat and mass transfer processes between the human body and the environment. The Computational Fluid Dynamics (CFD) numerical simulation has been a powerful tool in this investigation field. A combined simulation of a room and a thermal manikin has been developed in the FLUENT code. Using a manikin with real dimensions, divided into parts with different temperatures, seems important to give accurate fluid flow and moisture distributions.

Sign in / Sign up

Export Citation Format

Share Document