Spray Characteristics of a Spill-Return Airblast Atomizer

1989 ◽  
Vol 111 (1) ◽  
pp. 63-69 ◽  
Author(s):  
X. F. Dai ◽  
A. H. Lefebvre ◽  
J. Rollbuhler
Keyword(s):  
Drop Size ◽  
Cone Angle ◽  
Working Fluid ◽  
Air Velocity ◽  
Spray Characteristics ◽  
Spray Cone Angle ◽  
Liquid Distribution ◽  
Spray Cone ◽  
Liquid Injection ◽  
Bypass Ratio

The spray characteristics of a spill-return airblast atomizer are examined using water as the working fluid. Measurements of mean drop size, drop size distribution, spray cone angle, and circumferential liquid distribution are carried out over wide ranges of liquid injection pressures and atomizing air velocities. Generally it is found that an increase in nozzle bypass ratio worsens the atomization quality and widens the spray cone angle. Increase in airblast air velocity may improve or impair atomization quality depending on whether it increases or decreases the relative velocity between the liquid and the surrounding air. Airblast air can also be used to modify the change in spray cone angle that normally accompanies a change in bypass ratio.

Influence of Geometric Features on the Performance of Pressure-Swirl Atomizers

1990 ◽  
Vol 112 (4) ◽  
pp. 579-584 ◽  
Author(s):  
S. K. Chen ◽  
A. H. Lefebvre ◽  
J. Rollbuhler
Keyword(s):  
Drop Size ◽  
Cone Angle ◽  
Diameter Ratio ◽  
Working Fluid ◽  
Spray Characteristics ◽  
Spray Cone Angle ◽  
Liquid Distribution ◽  
Spray Cone ◽  
Pressure Swirl ◽  
Discharge Orifice

The spray characteristics of several different simplex pressure-swirl nozzles are examined using water as the working fluid. Measurements of mean drop size, dropsize distribution, effective spray cone angle, and circumferential liquid distribution are carried out over wide ranges of injection pressure. Eight different nozzles are employed in order to achieve a wide variation in the length/diameter ratio of the final discharge orifice. Generally, it is found that an increase in discharge orifice length/diameter ratio (lo/do) increases the mean drop size in the spray and reduces the spray cone angle. The circumferential liquid distribution is most uniform when lo/do=2. If lo/do is raised above or lowered below this optimum value, the circumferential uniformity of the liquid distribution is impaired. The observed effects of lo/do on spray characteristics are generally the same regardless of whether the change in lo/do is accomplished by varying lo or do.

Atomization Characteristics of Jatropha-Derived Alternative Aviation Fuels From Aircraft Engine Injector

2017 ◽  
Author(s):  
Ramachandran Sakthikumar ◽  
Deivandren Sivakumar ◽  
B. N. Raghunandan ◽  
John T. C. Hu
Keyword(s):  
Size Distribution ◽  
Drop Size ◽  
Cone Angle ◽  
Fuel Spray ◽  
Jet Fuels ◽  
Spray Characteristics ◽  
Spray Cone Angle ◽  
Spray Cone ◽  
Atmospheric Air ◽  
Atomization Characteristics

Search for potential alternative jet fuels is intensified in recent years to meet stringent environmental regulations imposed to tackle degraded air quality caused by fossil fuel combustion. The present study describes atomization characteristics of blends of jatropha-derived biofuel with conventional aviation kerosene (Jet A-1) discharging into ambient atmospheric air from a dual-orifice atomizer used in aircraft engines. The biofuel blends are characterized in detail and meet current ASTM D7566 specifications. The experiments are conducted by discharging fuel spray into quiescent atmospheric air in a fuel spray booth to measure spray characteristics such as fuel discharge behavior, spray cone angle, drop size distribution and spray patternation at six different flow conditions. The characteristics of spray cone angle are obtained by capturing images of spray and the measurements of spray drop size distribution are obtained using laser diffraction particle analyzer (LDPA). A mechanical patternator system comprising 144 measurement cells is used to deduce spray patternation at different location from the injector exit. A systematic comparison on the atomization characteristics between the sprays of biofuel blends and the 100% Jet A-1 is presented. The measured spray characteristics of jatropha-derived alternative jet fuels follow the trends obtained for Jet A-1 sprays satisfactorily both in qualitative and quantitative terms.

scholarly journals Experimental Study of Spray Characteristics of Kerosene-Ethanol Blends from a Pressure-Swirl Nozzle

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Tao Zhang ◽  
Bo Dong ◽  
Xun Zhou ◽  
Linan Guan ◽  
Weizhong Li ◽  
...  
Keyword(s):  
Discharge Coefficient ◽  
Cone Angle ◽  
Injection Pressure ◽  
Spray Characteristics ◽  
Spray Cone Angle ◽  
Spray Cone ◽  
Breakup Length ◽  
Ethanol Blends ◽  
Pressure Swirl ◽  
Spray Velocity

Partial replacement of kerosene by ethanol in a gas turbine is regarded as a good way to improve the spray quality and reduce the fossil energy consumption. The present work is aimed at studying the spray characteristics of kerosene-ethanol blends discharging from a pressure-swirl nozzle. The spray cone angle, discharge coefficient, breakup length, and velocity distribution are obtained by particle image velocimetry, while droplet size is acquired by particle/droplet imaging analysis. Kerosene, E10 (10% ethanol, 90% kerosene), E20 (20% ethanol, 80% kerosene), and E30 (30% ethanol, 70% kerosene) have been considered under the injection pressure of 0.1–1 MPa. The results show that as injection pressure is increased, the discharge coefficient and breakup length decrease, while the spray cone angle, drop size, and spray velocity increase. Meanwhile, the drop size decreases and the spray velocity increases with ethanol concentration when the injection pressure is lower than 0.8 MPa. However, the spray characteristics are not affected obviously by the ethanol concentration when the injection pressure exceeds 0.8 MPa. A relation to breakup length for kerosene-ethanol blends is obtained. The findings demonstrate that the adding of ethanol into kerosene can promote atomization performance.

Impacts of duct inner diameter and standoff distance on macroscopic spray characteristics of ducted fuel injection under non-vaporizing conditions

2020 ◽  
pp. 146808742091471
Author(s):  
Feng Li ◽  
Chia-fon Lee ◽  
Ziman Wang ◽  
Yiqiang Pei ◽  
Guoxiang Lu
Keyword(s):  
Large Scale ◽  
Fuel Injection ◽  
Soot Formation ◽  
Cone Angle ◽  
Mie Scattering ◽  
Standoff Distance ◽  
Spray Characteristics ◽  
Spray Cone Angle ◽  
Spray Cone ◽  
Inner Diameter

Ducted fuel injection spray is a new technology for reducing soot formation in heavy-duty diesel engines. In this work, the ducted fuel injection spray characteristics with different duct inner diameters and different standoff distances were investigated and compared with free spray. Duct inner diameter ranged from 1.5 to 4 mm, and standoff distance varied between 0.9 and 4.9 mm. Mie-scattering optical technique was used to characterize spray characteristics under various injection pressures in a constant-volume spray chamber. Ambient gas pressure of up to 6 MPa when spraying. The results showed that ducted fuel injection spray with smaller duct has better spray diffusion compared to those of ducted fuel injection sprays with larger ducts and free spray from the perspectives of spray tip penetration, spray cone angle and spray area. Increasing standoff distance could increase spray velocity. Ducted fuel injection spray with smaller duct formed a mushroom-shaped head and large-scale vortex flow close to the duct outlet. All the advantages of ducted fuel injection spray with smaller duct are interpreted as evidence of improving fuel–gas mixing quality significantly.

Effect of Injection Parameters on the Spray Characteristics of DME Fuel

2006 ◽  
Author(s):  
Bong Woo Ryu ◽  
Seung Hwan Bang ◽  
Hyun Kyu Suh ◽  
Chang Sik Lee
Keyword(s):  
Dimethyl Ether ◽  
Diesel Fuel ◽  
Cone Angle ◽  
Injection Pressure ◽  
Injection Rate ◽  
Spray Characteristics ◽  
Spray Cone Angle ◽  
Spray Cone ◽  
Injection Duration ◽  
Injection Parameters

The purpose of this study is to investigate the effect of injection parameters on the injection and spray characteristics of dimethyl ether and diesel fuel. In order to analyze the injection and spray characteristics of dimethyl ether and diesel fuel with employing high-pressure common-rail injection system, the injection characteristics such as injection delay, injection duration, and injection rate, spray cone angle and spray tip penetration was investigated by using the injection rate measuring system and the spray visualization system. In this work, the experiments of injection rate and spray visualization are performed at various injection parameters. It was found that injection quantity was decreased with the increase of injection pressure at the same energizing duration and injection pressure In the case of injection characteristics, dimethyl ether showed shorter of injection delay, longer injection duration and lower injected mass flow rate than diesel fuel in accordance with various energizing durations and injection pressures. Also, spray development of dimethyl ether had larger spray cone angle than that of diesel fuel at various injection pressures. Spray tip penetration was almost same development and tendency regardless of injection angles.

Experimental Study on Diesel Engine and Analysis the Spray Characteristics of Diesel and Biodiesel by Varying Injection Pressure

2014 ◽  
Vol 984-985 ◽  
pp. 932-937 ◽  
Author(s):  
Palani Raghu ◽  
M. Senthamil Selvan ◽  
K. Pitchandi ◽  
N. Nallusamy
Keyword(s):  
Experimental Study ◽  
Diesel Engine ◽  
Weber Number ◽  
Direct Injection ◽  
Cone Angle ◽  
Injection Pressure ◽  
Injection Velocity ◽  
Spray Characteristics ◽  
Spray Cone Angle ◽  
Spray Cone

— The spray characteristic of the injected fuel is mainly depends upon fuel injection pressure, temperature, ambient pressure, fuel viscosity and fuel density. An experimental study was conducted to examine the effect of injection pressure on the spray was injected into direct injection (DI) diesel engine in the atmospheric condition. In Diesel engine, the window of 20 mm diameter hole and the transparent quartz glass materials were used for visualizing spray characteristics of combustion chamber at right angle triangle position. The varying Injection pressure of 180 - 240 bar and the engine was hand cranked for conducting the experiments. Spray characteristics for Jatropha oil methyl ester (JOME) and diesel were studied experimentally. Spray tip penetration and spray cone angle were measured in a combustion chamber of Direct Injection diesel engine by employing high speed Digital camera using Mie Scattering Technique and ImageJ software. The study shows the JOME gives longer spray tip penetration and smaller spray cone angle than those of diesel fuels. The Spray breakup region (Reynolds number, Weber number), Injection velocity and Sauter Mean Diameter (SMD) were determined for diesel and JOME. SMD decreases for JOME than diesel and the Injection velocity, Reynolds Number, Weber Number Increases for JOME than diesel.

Influence of Ambient Air Pressure on Pressure-Swirl Atomization

1987 ◽  
Author(s):  
X. F. Wang ◽  
A. H. Lefebvre
Keyword(s):  
Drop Size ◽  
Cone Angle ◽  
Ambient Air ◽  
Air Pressure ◽  
Spray Angle ◽  
Flow Number ◽  
Spray Cone Angle ◽  
Spray Cone ◽  
Continuous Increase ◽  
Pressure Swirl

The spray characteristics of six simplex atomizers are examined in a pressure vessel using a standard light diffraction technique. Attention is focused on the effects of liquid properties, nozzle flow number, spray cone angle, and ambient air pressure on mean drop size and drop-size distribution. For all nozzles and all liquids it is found that continuous increase in air pressure above the normal atmospheric value causes the SMD to first increase up to a maximum value and then decline. An explanation for this characteristic is provided in terms of the measurement technique employed and the various competing influences on the overall atomization process. The basic effect of an increase in air pressure is to improve atomization, but this trend is opposed by contraction of the spray angle which reduces the relative velocity between the drops and the surrounding air, and also increases the possibility of droplet coalescence.

Experimental study of spray characteristics of biodiesel blending with diethyl carbonate in a common rail injection system

2017 ◽  
Vol 233 (2) ◽  
pp. 249-262 ◽  
Author(s):  
Wei Fu ◽  
Lanbo Song ◽  
Tao Liu ◽  
Qizhao Lin
Keyword(s):  
Cone Angle ◽  
Injection Pressure ◽  
Injection System ◽  
Diethyl Carbonate ◽  
Spray Characteristics ◽  
Projected Area ◽  
Spray Cone Angle ◽  
Spray Cone ◽  
Common Rail Injection System ◽  
Common Rail Injection

The objective of this paper is to investigate the spray macroscopic characteristics of biodiesel, diethyl carbonate (DEC)-biodiesel blends and diesel fuel based on a common-rail injection system. The spray tip penetration, spray cone angle and the spray projected area were measured through a high-speed photography method. The experimental results reveal that injection pressure and ambient pressure have significant effects on the spray characteristics. Higher injection pressure makes the spray tip penetration increase, while higher back pressure inside the chamber leads to the enlargement of the spray cone angle. The addition of DEC causes the blends fuels to have a shorter penetration and larger spray projected area, which reveals the potential capacity to improve the atomization process compared with biodiesel. The estimation of spray droplet size indicates that DEC30 generates a smaller Sauter mean diameter (SMD) because of its lower surface tension and viscosity. Model predictions were illustrated and compared with current work.

Macroscopic spray characteristics of long-chain alcohol-biodiesel fuels in a constant volume chamber

2017 ◽  
Vol 232 (2) ◽  
pp. 195-207 ◽  
Author(s):  
Fengyu Li ◽  
Bolun Yi ◽  
Lanbo Song ◽  
Wei Fu ◽  
Tao Liu ◽  
...  
Keyword(s):  
Cone Angle ◽  
Spray Characteristics ◽  
Spray Cone Angle ◽  
Spray Cone ◽  
Chain Alcohol ◽  
Biodiesel Blends ◽  
Spray Tip Penetration ◽  
Mixing Ratios ◽  
Long Chain Alcohol ◽  
Long Chain

In this research, three basic macroscopic spray characteristics (spray tip penetration, spray cone angle, and spray area) of long-chain alcohol-biodiesel blends were studied to investigate the differences of macroscopic spray characteristics of long-chain alcohol-biodiesel blends with different mixing ratios and to further investigate the effects of blending long-chain alcohols into biodiesel on the spray characteristics. Two kinds of long-chain alcohols, n-butanol, and n-pentanol, were selected to study effects of difference kinds of long-chain alcohols on macroscopic spray characteristics of long-chain alcohol-biodiesel blends. Results show that with the increase of proportion of n-butanol or n-pentanol in blends, spray tip penetration decreased while spray cone angle and spray area increased; in terms of the effects brought by different long-chain alcohols, n-pentanol-biodiesel blends showed slightly longer spray tip penetration, smaller spray cone angle and smaller spray area compared to n-butanol-biodiesel blends in the same mixing ratios, and the difference trends between those two kinds blends could easily be opposite due to the very similar properties of n-butanol and n-pentanol. Furthermore, a modified spray tip penetration model was proposed based on previous model and showed good agreement with experimental results.

Experimental Study on Spray Characteristics of Diesel Engines and Analysis of Fuel Dripping Phenomenon

2014 ◽  
Vol 1078 ◽  
pp. 271-275 ◽  
Author(s):  
Yu Qiang Wu ◽  
Qian Wang ◽  
Zhi Sheng Gao ◽  
Zhou Rong Zhang ◽  
Li Ming Dai
Keyword(s):  
Experimental Study ◽  
High Speed ◽  
Cone Angle ◽  
Digital Camera ◽  
Injection Pressure ◽  
Fuel Mixture ◽  
Long Distance ◽  
Spray Characteristics ◽  
Spray Cone Angle ◽  
Spray Cone

Experimental study on macroscopic spray characteristics of a certain type of domestic common rail injectors under the conditions of different injection pressures was carried out through a high-speed digital camera. Furthermore, a fuel dripping phenomenon at the end stage of injection was observed through the high-speed digital camera equipped with a long-distance microscope, and a further analysis of the phenomenon was made. The results show the increase in the injection pressure can evidently enhance spray cone angle and expand the scope of spray field in combustion chamber, which is conducive to air-fuel mixture. The spray cone angle during the development spray shows a double-peak shape. And the long response-time of seating of solenoid valve core that disables the injection cutting off in time is one of factors causing fuel dripping phenomenon.

Sign in / Sign up

Export Citation Format

Share Document