scholarly journals Penetration and Break-Up Studies of Discrete Liquid Jets in Cross Flowing Airstreams

1982 ◽  
Author(s):  
G. A. Hussein ◽  
A. K. Jasuja ◽  
R. S. Fletcher
Keyword(s):  
Atmospheric Pressure ◽  
Orifice Diameter ◽  
Liquid Jets ◽  
Liquid Jet ◽  
Sauter Mean Diameter ◽  
Normal Atmospheric Pressure ◽  
Penetration Data ◽  
Penetration Profile ◽  
Breakup Data ◽  
Light Scattering Technique

Penetration and breakup characteristics of a discrete liquid jet injected into a high-velocity cross flowing airstream were investigated as a basis of plain-jet airblast atomizer design. The main variables covered in this phase were, airstream velocity (from about 35 to 150 m/s), liquid jet velocity (from about 5 to 25 m/s) and injection orifice diameter (from about 0.5 to 2.5 mm). The tests were conducted under conditions of normal atmospheric pressure and temperature using still photography for penetration profile and a laser light scattering technique for mean dropsize determination. The experimental penetration data is shown to agree, reasonably accurately, with a relatively simple model developed in the paper. The analysis of the experimental breakup data reveals the airstream velocity as exercising the strongest influence upon Sauter Mean Diameter.

Penetration and Break-Up Behaviour of a Discrete Liquid Jet in a Cross Flowing Airstream: A Further Study

1983 ◽  
Author(s):  
G. A. Hussein ◽  
A. K. Jasuja ◽  
R. S. Fletcher
Keyword(s):  
Orifice Diameter ◽  
Liquid Jet ◽  
Liquid Density ◽  
Injection Angle ◽  
First Results ◽  
Normal Atmospheric Pressure ◽  
Break Up ◽  
Penetration Data ◽  
Penetration Profile ◽  
Light Scattering Technique

Penetration and break-up characteristics of a discrete liquid jet injected into a high velocity cross flowing airstream were examined as a basis of plain-jet airblast atomizer design. The first results of this program, detailed in (4), covered the effects of liquid jet/airstream velocities and the injection orifice diameter. The results presented here cover the effects of liquid viscosity (0.001 to 0.125 Ns/m2), liquid surface tension (0.027 to 0.074 N/m), liquid density (812 to 1830 Kg/m3), the liquid jet injection angle (30 to 90 degrees) and the orifice length-to-diameter ratio (5 to 14). These tests were carried out under normal atmospheric pressure and temperature conditions using still photography for penetration profile and a laser light scattering technique for mean dropsize determination. The experimental penetration data is shown to agree reasonably accurately, with the simple model developed before (see (4)). The analysis of the experimental mean dropsize data collected in this study leads to the development of the following correlation SMD = 1.206 σ ℓ V a 2 0.6 d j o 0.4 + 0.072 μ ℓ 2 σ ℓ ρ ℓ 0.45 d j o 0.55

Effect of Injector Geometry Variables Upon the Spray Performance of a Plain-Jet Airblast Atomizer

1985 ◽  
Author(s):  
S. G. Shaw ◽  
A. K. Jasuja
Keyword(s):  
Atmospheric Pressure ◽  
Drop Size ◽  
Laser Light ◽  
Laser Light Scattering ◽  
Liquid Jets ◽  
Liquid Jet ◽  
Scattering Technique ◽  
Atomization Performance ◽  
Light Scattering Technique ◽  
Quality Measurements

This paper presents the results of a study into the effect that liquid orifice orientation and scale have upon the drop-size performance of a plain-jet airblast atomizer featuring the injection of multiple liquid jets into a swirling airstream. Tests were conducted on water at near atmospheric pressure and temperature conditions using the well-established laser light scattering technique for spray quality measurements. The results presented in the paper reveal that the angular orientation of the liquid orifice, both in longitudinal and radial directions has a noticeable impact upon the atomization performance and exhibits scope for attaining further worthwhile reductions in drop-size relative to the multiple, transversely injected liquid jet configuration.

Simulation of Laminar Liquid Jets in Gaseous Crossflow Before the Onset of Primary Breakup

2011 ◽  
Author(s):  
C.-L. Ng ◽  
K. A. Sallam
Keyword(s):  
Experimental Data ◽  
Fuel Injection ◽  
Liquid Jets ◽  
Liquid Jet ◽  
Jet Breakup ◽  
Primary Breakup ◽  
Density Ratios ◽  
First Time ◽  
Two Sides ◽  
Reduced Pressures

The deformation of laminar liquid jets in gaseous crossflow before the onset of primary breakup is studied motivated by its application to fuel injection in jet afterburners and agricultural sprays, among others. Three crossflow Weber numbers that represent three different liquid jet breakup regimes; column, bag, and shear breakup regimes, were studied at large liquid/gas density ratios and small Ohnesorge numbers. In each case the liquid jet was simulated from the jet exit and ended before the location where the experimental data indicated the onset of breakup. The results show that in column and bag breakup, the reduced pressures along the sides of the jet cause the liquid to move to the sides of the jet and enhance the jet deformation. In shear breakup, the flattened upwind surface pushes the liquid towards the two sides of the jet and causing the gaseous crossflow to separate near the edges of the liquid jet thus preventing further deformation before the onset of breakup. It was also found out that in shear breakup regime, the liquid phase velocity inside the liquid jet was large enough to cause onset of ligament formation along the jet side, which was not the case in the column and bag breakup regimes. In bag breakup, downwind surface waves were observed to grow along the sides of the liquid jet triggered a complimentary experimental study that confirmed the existence of those waves for the first time.

Research of Water Damage Resistance Performance of CAM in Low Temperature Condition

2013 ◽  
Vol 723 ◽  
pp. 157-162
Author(s):  
Jian Li ◽  
Qu Chao ◽  
He Ping
Keyword(s):  
Low Temperature ◽  
Atmospheric Pressure ◽  
Asphalt Pavement ◽  
Natural World ◽  
Chloride Salt ◽  
The Road ◽  
Normal Atmospheric Pressure ◽  
Water Damage ◽  
Resistance Performance ◽  
Complex Polymer

Under normal atmospheric pressure conditions, volume suddenly increases about 11% when the water freezes and decreased when the ice melts. The pressure can reach up to 2500 times of atmospheric pressure in the closed space when the water freezing. This is a very important characteristic of the natural world and the industrial. In low temperature condition, the snow on the pavement is easy to melt and freeze, and it will affect the road safety, increase the cracking of the road and accelerate asphalt pavement water damage. Bitumen is a mixture consisting of some extremely complex polymer hydrocarbons and hydrocarbon derivatives of non-metallic (oxygen, sulfur, nitrogen). Deicing salt is used to prevent freezing in that area, chloride salt is its main ingredient. When the water melting point reduced, it is not easy to icing but to penetrate the asphalt pavement. If the temperature is continued to reduce, salt solution will still freezing. At last, the pavement will form water damage in repeated freeze-thaw cycles conditions.

scholarly journals Effects of Asymmetric Gas Distribution on the Instability of a Plane Power-Law Liquid Jet

Energies ◽  
2018 ◽  
Vol 11 (7) ◽  
pp. 1854 ◽  
Author(s):  
Jin-Peng Guo ◽  
Yi-Bo Wang ◽  
Fu-Qiang Bai ◽  
Fan Zhang ◽  
Qing Du
Keyword(s):  
Power Law ◽  
Liquid Velocity ◽  
Linear Instability ◽  
Liquid Jets ◽  
Liquid Jet ◽  
Critical Curves ◽  
Jet Breakup ◽  
Plane Jets ◽  
Gas Space ◽  
Aerodynamic Asymmetry

As a kind of non-Newtonian fluid with special rheological features, the study of the breakup of power-law liquid jets has drawn more interest due to its extensive engineering applications. This paper investigated the effect of gas media confinement and asymmetry on the instability of power-law plane jets by linear instability analysis. The gas asymmetric conditions mainly result from unequal gas media thickness and aerodynamic forces on both sides of a liquid jet. The results show a limited gas space will strengthen the interaction between gas and liquid and destabilize the power-law liquid jet. Power-law fluid is easier to disintegrate into droplets in asymmetric gas medium than that in the symmetric case. The aerodynamic asymmetry destabilizes para-sinuous mode, whereas stabilizes para-varicose mode. For a large Weber number, the aerodynamic asymmetry plays a more significant role on jet instability compared with boundary asymmetry. The para-sinuous mode is always responsible for the jet breakup in the asymmetric gas media. With a larger gas density or higher liquid velocity, the aerodynamic asymmetry could dramatically promote liquid disintegration. Finally, the influence of two asymmetry distributions on the unstable range was analyzed and the critical curves were obtained to distinguish unstable regimes and stable regimes.

scholarly journals The influence of argon gas flow in the killing of staphylococcus epidermidis bacteria

2018 ◽  
Vol 16 (36) ◽  
pp. 134-139
Author(s):  
Ahmed Mahmoud Shihab
Keyword(s):  
Staphylococcus Epidermidis ◽  
Atmospheric Pressure ◽  
Gas Flow ◽  
Biotechnological Applications ◽  
Plasma System ◽  
Argon Gas ◽  
Killing Rate ◽  
Normal Atmospheric Pressure ◽  
Non Thermal Plasma

In this research, non-thermal plasma system of argon gas is designed to work at normal atmospheric pressure and suitable for work in medical and biotechnological applications. This technique is applied in the treatment of the Staphylococcus epidermidis bacteria and show the role of the flow rate of Argon gas on the killing rate of bacteria, and it obtained a 100 % killing rate during the time of 5 minutes at the flow Argon gas of 5 liters/ min.

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