Spray Drop Size and Velocity Measurements Using the Phase/Doppler Particle Analyzer

1987 ◽  
Vol 4 (3-4) ◽  
Author(s):  
W.D. Bachalo ◽  
M.J. Houser
Keyword(s):  
Drop Size ◽  
Velocity Measurements ◽  
Phase Doppler Particle Analyzer

Drop Size and Velocity Measurements in Bio-Oil Sprays Produced by the Flow-Blurring Injector

2011 ◽  
Author(s):  
Benjamin M. Simmons ◽  
Ajay K. Agrawal
Keyword(s):  
Drop Size ◽  
Operating Conditions ◽  
Diesel Spray ◽  
Mass Ratio ◽  
Velocity Measurements ◽  
Sauter Mean Diameter ◽  
Atomization Process ◽  
Radial Profiles ◽  
Bio Oil ◽  
Phase Doppler Particle Analyzer

This study seeks to assess the performance of cold sprays of refined soybean oil produced by the Flow-Blurring (FB) atomization process. A cold diesel spray is also investigated for comparison. Drop size and velocity measurements for different fuels and operating conditions are acquired by a Phase Doppler Particle Analyzer (PDPA). Results show that the pressure drop in the fuel and atomizing airline of the FB injector is independent of the fuel. Radial profiles of Sauter Mean Diameter (SMD) were however affected by the fuel properties. For an Air to Liquid mass Ratio (ALR) of 2.0, the average SMD at an axial plane was about 38 μm for the VO sprays and 34 μm for the diesel spray. Increasing the ALR to 4.0 decreased the SMD in the VO spray to about 32 μm.

Drop Size and Velocity Measurements in an Electrostatically Produced Hydrocarbon Spray

1998 ◽  
Vol 120 (3) ◽  
pp. 580-585 ◽  
Author(s):  
J. S. Shrimpton ◽  
A. J. Yule
Keyword(s):  
Velocity Component ◽  
Drop Size ◽  
Average Diameter ◽  
Low Flow ◽  
Drop Diameter ◽  
Specific Charge ◽  
Velocity Measurements ◽  
Axial Velocity Component ◽  
Flow Rates ◽  
Injection Techniques

Liquid hydrocarbons are difficult to atomize electrostatically at practical flow rates due to their high resistivities and low concentration of charge carriers. However special “charge injection” techniques have been used in this investigation to produce combustible sprays of oils. An experimental investigation of the drop size and velocity distributions within a charged kerosine spray is presented, using a PDA system and photographic methods. Bimodal size distributions are found with a central core of larger drops or ligament formations near the nozzle surrounded by a sheath of smaller drops. Because of the bimodal character the concept of average diameter for the spray is difficult to apply so that there is little practical use defining a relationship between mean drop diameter and mean specific charge without a knowledge of a relationship between charge and size of individual drops. Examination of the velocity component distributions showed the processes which control the two-zone characteristics of the spray. The larger drops have a high inertia and were less deflected by the space charge force within the spray and it is argued that the larger drops possess a smaller specific charge compared with the smaller drops which reinforces the tendency for the large drops to remain along the spray centreline. For the smaller drops the converse is the case, to the extent that at low flow rates their trajectories have a negligible axial velocity component and recirculation toward the earthed injector body is observed.

Measurement of drop size characteristics in annular centrifugal extractors using phase Doppler particle analyzer (PDPA)

2012 ◽  
Vol 90 (8) ◽  
pp. 985-997 ◽  
Author(s):  
T.V. Tamhane ◽  
J.B. Joshi ◽  
Kamachi Mudali ◽  
R. Natarajan ◽  
R.N. Patil
Keyword(s):  
Drop Size ◽  
Phase Doppler Particle Analyzer

Characterization of Water Mist Sprays Using a Phase-Doppler-Particle-Analyzer and an Iso-Kinetic Sampling Probe

Volume 4 ◽  
2004 ◽  
Author(s):  
Benjamin Ditch ◽  
Hong-Zeng Yu
Keyword(s):  
Drop Size ◽  
Water Drop ◽  
Water Discharge ◽  
Radial Distance ◽  
Water Mist ◽  
Size Spectrum ◽  
Size Distributions ◽  
Sampling Probe ◽  
Phase Doppler Particle Analyzer ◽  
Drop Size Distributions

A Phase-Doppler-Particle-Analyzer (PDPA) was used to screen candidate water mist nozzles for use in a scaling validation aimed to allow scaled-down testing of water mist systems. A custom-designed iso-kinetic sampling probe (IKSP) was developed to independently measure water mist fluxes at the same locations where PDPA measurements were made. Measurements were taken at two elevations in selected full-cone water mist sprays. The water drop size was found to increase with radial distance from the spray centerline, while the mean drop velocity and drop concentration decrease with radial distance. Gross drop size distributions of water mist sprays were derived from local drop size distributions and water fluxes measured in two spray cross sections. It was found that, for the water mist sprays investigated in this study, both Rosin-Rammler and log-normal distributions are required to correlate the entire drop size spectrum. In general, the agreement between the mist fluxes measured with the PDPA and iso-kinetic sampling was within 7% near the spray centerline. The selected nozzles show appropriate intended scaling in terms of the drop size, nozzle discharge pressure, and water discharge rate.

Size and Velocity Characterization of Asymmetric Twin-Fluid Nebulizer Sprays

2006 ◽  
Author(s):  
Celienid Lopez ◽  
Paul E. Sojka
Keyword(s):  
Drop Size ◽  
Operating Conditions ◽  
Air Injection ◽  
Velocity Measurements ◽  
Flow Rates ◽  
Exit Port ◽  
Axis Of Symmetry ◽  
First Time ◽  
Asymmetric Configuration

Drop size and velocity measurements were obtained for two nebulizers unique in their asymmetric configuration—a "quarter-moon" liquid exit port, whose axis of symmetry is located nearly co-axially with a circular air exit port. The two devices, a Mira Mist and an LB-30, are commercially available units originally designed for mass-spectrometry applications, but also useful for medicinal/pharmaceutical spray purposes. Sprays were characterized in terms of droplet velocity and size at a number of axial and radial positions. Measurements were performed using a Dantec DualPDA. Air injection pressures of 270 to 410 kPa (25 to 45 psig) and liquid flow rates of 75 to 1200 ml/hr were the operating conditions considered in this study. Water and ethanol were used as test fluids since their physical properties span the range of typical products. The results are useful because they show, for the first time, how sprays formed from such asymmetric devices evolve as they move away from the atomizer.

Sign in / Sign up

Export Citation Format

Share Document