scholarly journals Air-entrainment characteristics in a plunging water jet system using rectangular nozzles with rounded ends

Water SA ◽  
2004 ◽  
Vol 29 (1) ◽  
Author(s):  
Tamer Bagatur ◽  
Nusret Sekerdag
Keyword(s):  
Air Entrainment ◽  
Water Jet ◽  
Plunging Water Jet

scholarly journals The Effects of Downcomer Diameter on an Air Entrainment of Vertical Plunging Water Jet on The Water Surface

2021 ◽  
Vol 81 (2) ◽  
pp. 89-97
Author(s):  
Warjito ◽  
Ridho Irwansyah ◽  
Iqbal Yudianto ◽  
Leonardo Fabianto ◽  
Arya Amardani ◽  
...  
Keyword(s):  
High Speed ◽  
Qualitative Data ◽  
Bubble Formation ◽  
Air Entrainment ◽  
Water Jet ◽  
Water Desalination ◽  
Entrainment Rate ◽  
Clean Water ◽  
Depth Of Penetration ◽  
Plunging Water Jet

The difficulty in finding clean water is issued to become Indonesia’s problem in 2025. Seawater processing to produce clean water for commonly used or called water desalination will be a promising solution to solve the problem of clean water scarcity. One of the seawater desalination processes is to utilize micro-bubbles generated from air entrainment. Air entrainment is a phenomenon where the surrounding air is trapped in the water and forms a bubble. Using the vertical plunging jet setup will lead to bubble formation as a result of the collision between the vertical water jet and the pond surface below it. This study determines the effect of downcomer diameter on the parameters that influence the parameter of air entrainment quality by using a vertical plunging jet configuration. Some set up tools that support research consists of pumps, nozzle, downcomer, airflow meter, anemometer, and water pond. Results of the research are in the form of qualitative data such as videos and photos, by using a high-speed camera with backlighting. The qualitative data obtained will be processed with an image processing program to acquire quantitative data. The results of the study revealed that the downcomer diameter affects the air entrainment rate. On the other hand, jet velocity affects the area of dispersion and depth of penetration.

Air Entrainment by Plunging Water Jet

2004 ◽  
Vol 2004.41 (0) ◽  
pp. 59-60
Author(s):  
Yusuke MIZUTANI ◽  
Atsushi SASAKI ◽  
Masaharu MATSUBARA ◽  
Yoshiaki TSUCHIYA
Keyword(s):  
Air Entrainment ◽  
Water Jet ◽  
Plunging Water Jet

Experimental Characterization of Air-Entrainment in a Plunging Water Jet System Using Particle Image Velocimetry (PIV)

2010 ◽  
Author(s):  
Xiaoliang Qu ◽  
Afshin Goharzadeh ◽  
Lyes Khezzar ◽  
Arman Molki
Keyword(s):  
Particle Image Velocimetry ◽  
Free Surface ◽  
Particle Image ◽  
Air Entrainment ◽  
Water Jet ◽  
Experimental Characterization ◽  
Free Jet ◽  
Image Velocimetry ◽  
Plunging Water Jet

This paper presents a detailed experimental study of a plunging jet on a free liquid surface. An experimental characterization facility is designed and constructed for generating a vertical round water jet impinging on a free surface of a pool. The experimental analysis focuses on the jet penetration depth, its relation to impact velocity Vj and free jet length Lj. Present results are compared with previous studies. The flowmap for four different regimes, in terms of impact jet velocity is obtained. The details of the two-dimensional velocity field below the pool liquid free surface under a no-entrainment regime, is obtained using Particle Image Velocimetry (PIV) and reveals the entrainment behavior of the impinging jet flow below the interface.

Role of Nozzles with Air Holes in Air Entrainment by a Water Jet

2003 ◽  
Vol 38 (4) ◽  
pp. 785-795 ◽  
Author(s):  
M. Emin Emiroglu ◽  
Ahmet Baylar
Keyword(s):  
Experimental Study ◽  
Nozzle Exit ◽  
Negative Pressure ◽  
Air Entrainment ◽  
Water Jet ◽  
Entrainment Rate ◽  
Air Bubbles ◽  
Air Entrainment Rate ◽  
Plunging Water Jet

Abstract When a water jet impinges a pool of water at rest, air bubbles may be entrained and carried a distance below the pool's surface. This process is called plunging water jet entrainment and aeration. This paper describes an experimental study of the air entrainment rate of circular nozzles with and without air holes, and in particular, the effect of varying numbers and positions of air holes and distance between the location of the air holes and nozzle exit. A negative pressure occurred due to the air holes on the circular nozzles. This phenomenon affected air entrainment. The differences in air entrainment rate were related to changes in the jet shape. It was demonstrated that the air entrainment rates of the circular nozzles with air holes were significantly higher than those of circular nozzles without air holes.

Validation of NEPTUNE_CFD Module with Data of a Plunging Water Jet Entering a Free Surface

2009 ◽  
Vol 167 (1) ◽  
pp. 60-70 ◽  
Author(s):  
M. C. Galassi ◽  
D. Bestion ◽  
C. Morel ◽  
J. Pouvreau ◽  
F. D’Auria
Keyword(s):  
Free Surface ◽  
Water Jet ◽  
Plunging Water Jet

The Effect of Nozzle Type on Air Entrainment by Plunging Water Jets

2002 ◽  
Vol 37 (3) ◽  
pp. 599-612 ◽  
Author(s):  
Tamer Bagatur ◽  
Ahmet Baylar ◽  
Nusret Sekerdag
Keyword(s):  
Penetration Depth ◽  
Oxygen Transfer ◽  
Free Water ◽  
Air Entrainment ◽  
Water Jet ◽  
Transfer Efficiency ◽  
Entrainment Rate ◽  
Water Jets ◽  
Air Entrainment Rate ◽  
Oxygen Transfer Efficiency

Abstract In this study, for the plunging water jet aeration system using various inclined nozzle types, bubble penetration depth, air entrainment rate, water jet expansion, effect of water jet circumference at impact point, oxygen transfer coefficient and oxygen transfer efficiency which changed depending on the water jet velocity, were researched in an air-water system. Numerous studies were conducted with circular nozzles. The present study describes new experiments performed with different nozzle types. Three types of nozzles were examined, i.e., those with circular, ellipse and rectangle duct with rounded ends. Experimental results showed that water jets produced with ellipse and rectangle duct with rounded ends nozzles have very different flow characteristics, entrainment patterns on free water jet surface, and submerged water jet region within the receiving tank. Higher air entrainment rate and oxygen transfer efficiency was observed in the rectangle duct with rounded ends nozzle due to water jet expansion. Bubble penetration depth, however, is lower for the rectangle duct with rounded ends nozzle than for the other nozzles. The ellipse nozzle provided the highest bubble penetration depth. These results showed that it is appropriate to use ellipse nozzle in aeration of deep pool and rectangle duct with rounded ends nozzle in the applications where high bubble concentration is desirable.

Acoustic measurements of air entrainment by a plunging free water jet

1999 ◽  
Vol 105 (2) ◽  
pp. 1254-1255
Author(s):  
Thomas R. Hahn ◽  
Thomas K. Berger ◽  
Michael J. Buckingham
Keyword(s):  
Free Water ◽  
Air Entrainment ◽  
Water Jet ◽  
Acoustic Measurements
Sign in / Sign up

Export Citation Format

Share Document