0
Flows in Complex Systems

Characteristics of Mean Droplet Size Produced by Spinning Disk Atomizers

[+] Author and Article Information
Mahmoud Ahmed1

 Mechanical Engineering Department,Assiut University, Assiut 71516, Egyptaminism@aun.edu.eg

M. S. Youssef

 Mechanical Engineering Department,Assiut University, Assiut 71516, Egypt

1

Corresponding author.

J. Fluids Eng 134(7), 071103 (Jun 21, 2012) (9 pages) doi:10.1115/1.4006819 History: Received December 06, 2011; Revised May 05, 2012; Published June 21, 2012; Online June 21, 2012

Characteristics of mean droplet size of spray produced by spinning disk atomizers were experimentally investigated. The phase-doppler particle analyzer (PDPA) was used to measure the droplet size of water spray in the downstream distance along the spray trajectory. Effects of various operating conditions on the mean diameter had been studied. The studied variables were: the rotational speed in the range of 838 to 1677 rad/s (8,000–16,000 rpm), the liquid flow rate in the range of 0.56 to 2.8 × 10−6 m3 /s (2–10 L/h), the disk diameter in the range of 0.04 to 0.12 m, and the downstream tangential distance along the spray trajectory of up to 0. 24 m. The Sauter mean diameter (d32 ) was used to represent the mean of generated spray droplet sizes. The results indicated that the Sauter mean diameter can be correlated with dimensionless groups, such as the Reynolds number, Weber number, flow coefficient, and the ratio of downstream distance to disk diameter. Based on this correlation, it was found that the Sauter mean diameter (d32 ) increases as the downstream tangential distance, and liquid flow rate increase. Similarly, a decrease of rotational speed and disk diameter results in an increase in the Sauter mean diameter (d32 ). A comparison between the developed correlation and correlations obtained by other researchers has been presented and discussed in detail.

Copyright © 2012 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

A schematic diagram of the experimental setup. 1-AC power supply, 2-stabilizer, 3-variac, 4-avometer, 5-AC variable speed motor with tacho, 6-disk, 7-plate, 8-variable nozzle diameter, 9-flow meter, 10-pressure regulator, 11-3-D mechanism, 12-pressure vessel, 13-main source valve, 14-pressure relief valve, 15-compressed air, 16-receiver, 17-transmitter, 18-oscilloscope, 19-signal processor, 20-computer, 21-printer.

Grahic Jump Location
Figure 2

Comparison between the breakup regimes defined by Eqs. 7,8,9,10, and the present experimental data for (a) D = 0.04 m, (b) D = 0.08 m, and (c) D = 0.12 m

Grahic Jump Location
Figure 3

Variation of the measured mean droplet sizes d32 and the predicted values. Note for symbols, the first number presents the rotational speed, rad/s, and the second number presents the flow rate, m3 /s. For D = 0.04 m: (

) 838-0.56E-6, ()1047-0.56E-6, () 1257-0.56E-6, () 1466-0.56E-6, () 1677-0.56E-6, () 838-1.1E-6, () 1047-1.1E-6, () 1257-1.1E-6, () 1466-1.1E-6, () 1677-1.1E-6, () 838-1.7E-6, () 1047-1.7E-6, () 1257-1.7E-6, () 1466-1.7E-6, ()1677-1.7E-6, () 838-2.2E-6, () 1047-2.2E-6, () 1257-2.2E-6, () 1466-2.2E-6, () 1677-2.2E-6, () 838-2.8E-6, () 1047-2.8E-6, (̂) 1257-2.8E-6, (+)1466-2.8E-6, (−)1677-2.8E-6. For D = 0.08 m: () 838-0.56E-6, () 1047- 0.56E-6, () 1257-0.56E-6, () 1466-0.56E-6, () 1677-0.56E-6, () 838-1.1E-6, () 1047-1.1E-6, ()1257-1.1E-6, () 1466-1.1E-6, () 1677-1.1E-6, () 838-1.7E-6, () 1047-1.7E-6, () 1257-1.7E-6, () 1466-1.7E-6, () 1677-1.7E-6, () 838-2.2E-6, () 1047-2.2E-6, () 1257-2.2E-6, () 1466-2.2E-6, () 1677-2.2E-6, () 838-2.8E-6, (*) 1047-2.8E-6, () 1257-2.8E-6, () 1466-2.8E-6, () 1677-2.8E-6. For D = 0.12 m: (@) 838-0.56E-6, (#) 1047-0.56E-6, ($) 1257-0.56E-6, (%) 1466-0.56E-6, (̂) 838-1.1E-6, (&) 1047-1.1E-6, (*) 1257-1.1E-6, (-) 1466-1.1E-6, (+) 838-1.7E-6, (=) 1047-1.7E-6, (<) 1257-1.7E-6, (>) 1466-1.7E-6, (?) 838-2.2E-6, (!) 1047-2.2E-6, (“) 1257-2.2E-6, (a) 1466-2.2E-6, (b) 838-2.8E-6, (c) 1047-2.8E-6, (d) 1257-2.8E-6, (e) 1466-2.8E-6, (f) 1677-2.8E-6.

Grahic Jump Location
Figure 4

Measured and correlated values of Sauter mean diameter d32 at different diameters of spinning disk atomizers for (a) ω = 838 rad/s, and Q = 1.1 × 10−6 m3 /s, and (b) ω = 1466 rad/s, and Q = 1.1 × 10−6 m3 /s

Grahic Jump Location
Figure 5

Measured and correlateded values of Sauter mean diameter d32 at different diameters of spinning disk atomizers for ω = 1466 rad/s, and Q = 2.2 × 10−6 m3 /s

Grahic Jump Location
Figure 6

Measured and correlated values of Sauter mean diameter d32 at different rotational speeds of spinning disk atomizers for D = 0.12 m, and Q = 1.7 × 10−6 m3 /s

Grahic Jump Location
Figure 7

Measured and correlated values of Sauter mean diameter d32 at different rotational speeds of spinning disk atomizers for D = 0.12 m, and Q = 2.8 × 10−6 m3 /s

Grahic Jump Location
Figure 8

Measured and correlated values of Sauter mean diameter d32 at different liquid flow rates for (a) D = 0.04 m, ω = 1677 rad/s, and (b) D = 0.08 m, ω = 1677 rad/s

Grahic Jump Location
Figure 9

Measured and correlated values of Sauter mean diameter d32 at different liquid flow rates for (a) D = 0.08 m, ω = 838 rad/s, and (b) D = 0.08 m, ω = 1257 rad/s

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In