Characterization of fuel spray for a marine burner back-spill...
Transcript of Characterization of fuel spray for a marine burner back-spill...
![Page 1: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/1.jpg)
Characterization of fuel spray for a marine burner back-spill atomizer
Giovanni Cafaggi*
Co-Authors:
Peter Arendt Jensen
Peter Glarborg
Sønnik Clausen
Kim Dam-Johansen
* Corresponding author: [email protected]
![Page 2: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/2.jpg)
DTU Chemical Engineering, Technical University of Denmark
Agenda
30 May 20182
• Introduction to the project
• Spray characterization setup
• Selected results
• Conclusions and future work
![Page 3: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/3.jpg)
DTU Chemical Engineering, Technical University of Denmark 30 May 20183
Background
Project goals:
• Support the development of a new burner:
– Lower NOx emissions
– Multi-fuel capability
• Set up reliable CFD simulations to evaluate further improvements
![Page 4: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/4.jpg)
DTU Chemical Engineering, Technical University of Denmark 30 May 20184
CFD background and contribution
2% CO surface,fuel droplets in black
Temperature
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Num
ber
of
dro
ple
ts [
%]
Dro
ple
t m
ean d
iam
ete
r [µ
m]
Distance from the nozzle [mm]
Simulated droplet evaporation
Mean diameter
Evaporated Droplets
• Sensitivity to droplet size
and velocity.
• Range for experimental
spray measurements.
![Page 5: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/5.jpg)
DTU Chemical Engineering, Technical University of Denmark
Spray setup commissioning
30 May 20185
• CFD showed that the flame stability is highly dependant from the droplet size and velocity distributions.
• The setup has been built for direct measurements of both using optical imaging methods.
• The setup is able to reproduce the operating conditions of the atomizer in the full scale boiler (matching flows and operating pressures, spill-return nozzle).
![Page 6: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/6.jpg)
DTU Chemical Engineering, Technical University of Denmark
Pump
Tap water
Tank
Pressuregauge 1
Nozzle holder
Nozzle
Spray
Pressuregauge 2
Safety valve
Membrane tank
Flowmeter 1
Flow meter 2Backpressure
valve 2
Backpressure valve 1
Spray setup
30 May 20186
Nozzle section
Setup PID
Working nozzle
![Page 7: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/7.jpg)
DTU Chemical Engineering, Technical University of Denmark
Spray setup – measurement technology
• Led pulser (1μs), ccv camera, stereoscopic lens (2.5 μm resolution)
• Pairs of images to find droplet velocities
• Image analysis with in-house software
7
2.41mm
3.24mm
0.86mm
F. Cernuschi et al. 2017 [4]
30 May 2018
Imaging system
Observed volume
Pair of images 1 µs apart
![Page 8: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/8.jpg)
DTU Chemical Engineering, Technical University of Denmark
Spray setup – measurement technology
8
F. Cernuschi et al. 2017 [4]
2.41mm
3.24mm
0.86mm
• Led pulser (1μs), ccv camera, stereoscopic lens (2.5 μm resolution)
• Pairs of images to find droplet velocities
• Image analysis with in-house software
30 May 2018
Imaging system
Observed volume
Pair of images 1 µs apart
![Page 9: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/9.jpg)
DTU Chemical Engineering, Technical University of Denmark
Spray setup – measurement technology
• Led pulser (1μs), ccv camera, stereoscopic lens (2.5 μm resolution)
• Pairs of images to find droplet velocities
• Image analysis with in-house software
9
2.41mm
3.24mm
0.86mm
F. Cernuschi et al. 2017 [4]
30 May 2018
Imaging system
Observed volume
Pair of images 1 µs apart
![Page 10: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/10.jpg)
DTU Chemical Engineering, Technical University of Denmark
Spray setup – measurement technology
10
F. Cernuschi et al. 2017 [4]
2.41mm
3.24mm
0.86mm
• Led pulser (1μs), ccv camera, stereoscopic lens (2.5 μm resolution)
• Pairs of images to find droplet velocities
• Image analysis with in-house software
30 May 2018
Imaging system
Observed volume
Pair of images 1 µs apart
![Page 11: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/11.jpg)
DTU Chemical Engineering, Technical University of Denmark 30 May 201811
Images Extracted data
Spray setup - PostprocessingNumber based particle size distribution
at 15 mm radial distance
Droplet pairing criteria:
• Area
• Sharpness
• Position
![Page 12: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/12.jpg)
DTU Chemical Engineering, Technical University of Denmark 30 May 201812
Images Extracted data
Droplet pairing and analysis
Spray setup - PostprocessingNumber based particle size distribution
at 15 mm radial distance
![Page 13: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/13.jpg)
DTU Chemical Engineering, Technical University of Denmark
Spray setup - Results
30 May 201813
• Experimentally based data:
– Droplet velocity distribution
– Droplet density distribution
– Droplet size distribution
– Droplet volume fraction distribution
– Partial flow behaviour
![Page 14: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/14.jpg)
DTU Chemical Engineering, Technical University of Denmark
Spray setup - results
30 May 201814
• Experimentally based data:
– Droplet velocity distribution
– Droplet density distribution
– Droplet size distribution
– Droplet volume fraction distribution
– Partial flow behaviour
0
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30
0 50 100 150 200
Velo
city m
agnitude [
m/s
]
Distance from injection [mm]
Average droplet velocity from spray setup simulations and experiments
SS distance based
SS volume based
experiments
transient distance based
transient volume based
Preliminary spray setup CFD transient simulation
![Page 15: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/15.jpg)
DTU Chemical Engineering, Technical University of Denmark
• Experimentally based data:
– Droplet velocity distribution
– Droplet density distribution
– Droplet size distribution
– Droplet volume fraction distribution
– Partial flow behaviour
0
20
40
60
80
100
120
0 10 20 30 40 50 60
SMD
Spray setup - results
30 May 201815
66% load
Experimental results match the simulation regarding the stratification
of droplets according to their size
Simulations
Experimental measurements
33% load
100% load
[μm
]
Angle with spray axis [o]
Droplets diameters
![Page 16: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/16.jpg)
DTU Chemical Engineering, Technical University of Denmark
0.00E+00
5.00E-05
1.00E-04
1.50E-04
2.00E-04
0 10 20 30 40 50 60
Volume fraction
Spray setup - results
16
• Experimentally based data:
– Droplet velocity distribution
– Droplet density distribution
– Droplet size distribution
– Droplet volume fraction distribution
– Partial flow behaviour
Angle with spray axis [o]
[μm
][#
]
[-]
0
5
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35
0 10 20 30 40 50 60
Droplet in each image
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40
60
80
100
120
0 10 20 30 40 50 60
SMD
30 May 2018
0
5
10
15
20
25
30
35
0 10 20 30 40 50 60
Average velocity
[m/s
]
Angle with spray axis [o]
![Page 17: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/17.jpg)
DTU Chemical Engineering, Technical University of Denmark
0.00E+00
5.00E-05
1.00E-04
1.50E-04
2.00E-04
0 10 20 30 40 50 60
Volume fraction
Spray setup - results
17
• Experimentally based data:
– Droplet velocity distribution
– Droplet density distribution
– Droplet size distribution
– Droplet volume fraction distribution
– Partial flow behaviour
Angle with spray axis [o]
[μm
][#
]
[-]
0
5
10
15
20
25
30
35
0 10 20 30 40 50 60
Droplet in each image
0
20
40
60
80
100
120
0 10 20 30 40 50 60
SMD
30 May 2018
0
5
10
15
20
25
30
35
0 10 20 30 40 50 60
Average velocity
[m/s
]
Angle with spray axis [o]
![Page 18: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/18.jpg)
DTU Chemical Engineering, Technical University of Denmark
0.00E+00
5.00E-05
1.00E-04
1.50E-04
2.00E-04
0 10 20 30 40 50 60
Volume fraction
Spray setup - results
18
• Experimentally based data:
– Droplet velocity distribution
– Droplet density distribution
– Droplet size distribution
– Droplet volume fraction distribution
– Partial flow behaviour
Angle with spray axis [o]
[μm
][#
]
[-]
0
5
10
15
20
25
30
35
0 10 20 30 40 50 60
Droplet in each image
0
20
40
60
80
100
120
0 10 20 30 40 50 60
SMD
30 May 2018
0
5
10
15
20
25
30
35
0 10 20 30 40 50 60
Average velocity
[m/s
]
Angle with spray axis [o]
![Page 19: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/19.jpg)
DTU Chemical Engineering, Technical University of Denmark
0.00E+00
5.00E-05
1.00E-04
1.50E-04
2.00E-04
0 10 20 30 40 50 60
Volume fraction
Spray setup - results
19
• Experimentally based data:
– Droplet velocity distribution
– Droplet density distribution
– Droplet size distribution
– Droplet volume fraction distribution
– Partial flow behaviour
Angle with spray axis [o]
[μm
][#
]
[-]
0
5
10
15
20
25
30
35
0 10 20 30 40 50 60
Droplet in each image
0
20
40
60
80
100
120
0 10 20 30 40 50 60
SMD
30 May 2018
0
5
10
15
20
25
30
35
0 10 20 30 40 50 60
Average velocity
[m/s
]
Angle with spray axis [o]
![Page 20: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/20.jpg)
DTU Chemical Engineering, Technical University of Denmark
0.00E+00
5.00E-05
1.00E-04
1.50E-04
2.00E-04
0 10 20 30 40 50 60
Volume fraction
Spray setup - results
20
• Experimentally based data:
– Droplet velocity distribution
– Droplet density distribution
– Droplet size distribution
– Droplet volume fraction distribution
– Partial flow behaviour
Angle with spray axis [o]
[μm
][#
]
[-]
0
5
10
15
20
25
30
35
0 10 20 30 40 50 60
Droplet in each image
0
20
40
60
80
100
120
0 10 20 30 40 50 60
SMD
30 May 2018
0
5
10
15
20
25
30
35
0 10 20 30 40 50 60
Average velocity
[m/s
]
Angle with spray axis [o]
![Page 21: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/21.jpg)
DTU Chemical Engineering, Technical University of Denmark
0.00E+00
5.00E-05
1.00E-04
1.50E-04
2.00E-04
0 10 20 30 40 50 60
Volume fraction
Spray setup - results
21
• Experimentally based data:
– Droplet velocity distribution
– Droplet density distribution
– Droplet size distribution
– Droplet volume fraction distribution
– Partial flow behaviour
Angle with spray axis [o]
[μm
][#
]
[-]
0
5
10
15
20
25
30
35
0 10 20 30 40 50 60
Droplet in each image
0
20
40
60
80
100
120
0 10 20 30 40 50 60
SMD
30 May 2018
0
5
10
15
20
25
30
35
0 10 20 30 40 50 60
Average velocity
[m/s
]
Angle with spray axis [o]
![Page 22: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/22.jpg)
DTU Chemical Engineering, Technical University of Denmark
Spray setup - results
30 May 201822
• Experimentally based data:
– Droplet velocity distribution
– Droplet density distribution
– Droplet size distribution
– Droplet volume fraction distribution
– Partial flow behaviour
0
5
10
15
20
25
30
35
0 25 50 75 100 125 150 175
Droplet in each image
0
20
40
60
80
100
120
0 25 50 75 100 125 150 175
SMD
0.00E+00
5.00E-05
1.00E-04
1.50E-04
2.00E-04
0 25 50 75 100 125 150 175
Volume fraction
Angle scaled on highest coverage [%]
[μm
][#
]
[-]
0
5
10
15
20
25
30
35
0 25 50 75 100 125 150 175
Average velocity
Angle scaled on highest coverage [%]
[m/s
]
![Page 23: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/23.jpg)
DTU Chemical Engineering, Technical University of Denmark
Conclusions
• Measurements at different loads showed that it has little effect on particle size,
droplet concentration and volume fraction distribution.
• On the other hand, spray cone angle and velocity are heavily affected by
changes in load.
• Even if the volume fraction is low, there is a large number of droplet in the
hollow part of the cone.
• Data from the spray setup matched expectations and CFD simulations
23 30 May 2018
![Page 24: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/24.jpg)
DTU Chemical Engineering, Technical University of Denmark
Future work
• Further experiments should be carried out to observe spray characteristics at
various axial distances and to check if the CFD results are matched also further
away from the nozzle.
• Spray setup improvements to avoid droplet recirculation and avoid liquid spills
• Water/glycerol solutions with surfactants for the spray setup (viscosity and
surface tension): design of model fluids to evaluate spray characteristics of
different fuels
24 30 May 2018
![Page 25: Characterization of fuel spray for a marine burner back-spill …orbit.dtu.dk/files/148850665/Cafaggi_IFRF_2018... · 2018-06-06 · marine burner back-spill atomizer Giovanni Cafaggi*](https://reader031.fdocuments.in/reader031/viewer/2022022520/5b1cf7777f8b9a952f8baaff/html5/thumbnails/25.jpg)
DTU Chemical Engineering, Technical University of Denmark
Thank you for your attention