Experimental Study on the Aerodynamic Sealing of Air Curtains
Abstract
:1. Introduction
2. Methods
2.1. Analytical Model
- the momentum is conserved in the non-disturbed jet;
- the speed of the jet was assumed as uniform at the jet cross section; and
- the momentum balance is expressed by the product of the flow rate by the average speed (actually, this is not true and is only considered here to analyze the variables influencing the process; empirical correcting values will be afterwards deduced).
2.2. Experimental Water Modelling
3. Results and Discussion
3.1. Test Results
3.2. Analysis of the Influence of the Jet Nozzle Thickness on the Average Speed at the Door Opening
3.3. Analysis of the Influence of the Jet Angle
3.4. Influence of on the Average Speed at the Door Opening
3.5. Analytical Method
- The velocity at the opening is still necessary to avoid the spread of the contamination, when the jet is not active ();
- The jet angle exerts no influence if ; and
- No influence of the nozzle thickness was observed in the experiments.
4. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
Nomenclature
jet nozzle thickness | |
h | door height, |
jet momentum | |
momentum of the flow rate rejected to the contaminated side | |
momentum of the flow rate rejected to the non-contaminated side | |
momentum of the flow through the door | |
L | jet width |
jet flow rate at the nozzle | |
jet flow rate at the floor impingement zone | |
flow rate rejected to the contaminated side | |
flow rate rejected to the non-contaminated side | |
flow rate at the jet nozzle | |
jet flow rate | |
or U0 | average jet nozzle velocity |
average jet velocity at the floor impingement zone | |
average velocity of the flow rate rejected to the contaminated side | |
average velocity of the flow rate rejected to the non-contaminated side | |
or Ua | average velocity of the flow across the door |
average velocity of the flow across the door when | |
exhaust flow rate | |
w | door width |
X | jet length, longitudinal coordinate of the jet |
slope of the jet | |
kinematic viscosity |
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Test | Thickness of the Jet b0 (m) | Width of the Jet L (m) | Section of the Jet (m²) | Height of the Door h (m) | Width of the Door w (m) |
---|---|---|---|---|---|
57–88; 92–107 | 0.00125 | 0.1456 | 0.000182 | 0.125 | 0.125 |
89 | 0.00250 | 0.000364 | |||
90 | 0.00375 | 0.000546 | |||
91 | 0.00500 | 0.000728 |
Re | ||||
---|---|---|---|---|
1.70 | 0 | 1.20 | 0.077 | 2125 |
5 | 1.20 | 0.077 | ||
10 | 1.20 | 0.077 | ||
15 | 1.20 | 0.077 | ||
1.37 | 0 | 1.07 | 0.068 | 1710 |
5 | 1.07 | 0.068 | ||
10 | 1.07 | 0.069 | ||
15 | 1.07 | 0.069 | ||
0.98 | 0 | 0.84 | 0.054 | 1224 |
5 | 0.81 | 0.052 | ||
10 | 0.79 | 0.051 | ||
15 | 0.69 | 0.044 | ||
0.55 | 0 | 0.73 | 0.046 | 687 |
5 | 0.69 | 0.044 | ||
10 | 0.64 | 0.041 | ||
15 | 0.58 | 0.037 | ||
0.29 | 0 | 0.55 | 0.035 | 367 |
5 | 0.48 | 0.031 | ||
10 | 0.42 | 0.027 | ||
15 | 0.33 | 0.021 | ||
0.12 | 0 | 0.41 | 0.027 | 146 |
5 | 0.33 | 0.021 | ||
10 | 0.25 | 0.016 | ||
15 | 0.19 | 0.012 | ||
0.00 | - | 0.04 | 0.0026 | - |
Re | |||||
---|---|---|---|---|---|
0.29 | 15 | 0.33 | 0.021 | 367 | 0.00125 |
0.15 | 0.23 | 0.015 | 0.00250 | ||
0.10 | 0.20 | 0.013 | 0.00375 | ||
0.07 | 0.19 | 0.012 | 0.00500 |
Variable | Value |
---|---|
A | 0.0595 |
B | 1.00 |
C | 0.00 |
f | 1.05 |
j | 0.470 |
Variable | Value |
---|---|
A | 0.0564 |
B | 1.00 |
C | 0.0026 |
f | 1.00 |
j | 0.50 |
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Viegas, J.C.; Oliveira, F.; Aelenei, D. Experimental Study on the Aerodynamic Sealing of Air Curtains. Fluids 2018, 3, 49. https://doi.org/10.3390/fluids3030049
Viegas JC, Oliveira F, Aelenei D. Experimental Study on the Aerodynamic Sealing of Air Curtains. Fluids. 2018; 3(3):49. https://doi.org/10.3390/fluids3030049
Chicago/Turabian StyleViegas, João Carlos, Fernando Oliveira, and Daniel Aelenei. 2018. "Experimental Study on the Aerodynamic Sealing of Air Curtains" Fluids 3, no. 3: 49. https://doi.org/10.3390/fluids3030049
APA StyleViegas, J. C., Oliveira, F., & Aelenei, D. (2018). Experimental Study on the Aerodynamic Sealing of Air Curtains. Fluids, 3(3), 49. https://doi.org/10.3390/fluids3030049