Air-augmented waterjets derive their propulsion from compressed gas mixed directly into the main flow. The gas bubbles expand as the mixture passes through the pressure gradient of the convergent nozzle, and energy is imparted to the water from the air in a complex fashion. This experiment measures the exchange of air and water energy for three nozzles over a range of flowrates and void fractions using compressed air injected and mixed upstream of the nozzle entrance. Pressures and nozzle thrust are measured to examine flow changes. The results are compared with predictions from a one-dimensional bubbly flow model. The measured efficiencies are lower than or comparable to predicted values.

Issue Section:
Multiphase Flows
Keywords:
bubbles, jets, marine systems, nozzles, propulsion, two-phase flow
Topics:
Bubbles, Nozzles, Thrust, Water, Flow (Dynamics)
1.
Muench
,
R. K.
, and
Garrett
,
J. H.
, 1972, “
Review of Two-Phase Marine Propulsion
,”
AlAA/SNAME/USN Advanced Marine Propulsion Meeting
, Annapolis, MD, AIAA Paper No. 72-589.
2.
Tangren
,
R. F.
,
Dodge
,
C. H.
, and
Seifert
,
H. S.
, 1949, “
Compressibility Effects in Two-Phase Flow
,”
J. Appl. Phys.
0021-8979,
20
, pp.
637
–
645
.
Crossref
Search ADS
 
3.
Mottard
,
E. J.
, and
Shoemaker
,
E. J.
, 1961, “
Preliminary Investigation of an Underwater Ramjet Powered by Compressed Air
,”
NASA
, Report No. TN D-991.
4.
Pierson
,
J. D.
, 1965, “
An Application of Hydropneumatic Propulsion to Hydrofoil Craft
,”
J. Aircr.
0021-8669,
2
(
3
), pp.
250
–
254
.
Crossref
Search ADS
 
5.
Pallabazzer
,
R.
, 1968, “
Design Analysis of Gas-Turbine Powerplants for Two-Phase Hydropropulsion
,”
Seventh Symposium on Naval Hydrodynamics
, Office of Naval Research, Rome, Italy, pp.
1105
–
1171
.
6.
Witte
,
J. H.
, 1969, “
Predicted Performance of Large Water Ramjets
,” AIAA Paper No. 69-406.
7.
Amos
,
R. G.
,
Maples
,
G.
, and
Dyer
,
D. F.
, 1973, “
Thrust of an Air-Augmented Waterjet
,”
J. Hydronaut.
0022-1716,
7
(
2
), pp.
64
–
71
.
Crossref
Search ADS
 
8.
Stansell
,
J. F.
,
Maples
,
G.
, and
Dyer
,
D. F.
, 1976, “
Performance of Gas-Augmented Waterjet Propulsion System
,”
ASME Marine Propulsion, OED
, Vol.
2
, pp.
129
–
150
.
9.
Albagli
,
D.
, and
Gany
,
A.
, 2003, “
High Speed Bubbly Nozzle Flow With Heat, Mass, and Momentum Interactions
,”
Int. J. Heat Mass Transfer
0017-9310,
46
, pp.
1993
–
2003
.
Crossref
Search ADS
 
10.
Gany
,
A.
, 2004, “
Analysis of a New Thermodynamic Power Cycle for a Two-Phase Waterjet
,”
International Conference on Waterjet Propulsion 4
, RINA, London, UK.
11.
Tsai
,
J. -F.
,
Tse
,
C. -C.
,
Wang
,
S. -Y.
, and
Yeh
,
D. -C.
, 2005, “
Experimental Study on the Hydrodynamic Performance of a Two-Phase Nozzle for Waterjet Propulsion System
,”
International Conference on Fast Sea Transportation, FAST 2005
, St. Petersburg, Russia.
12.
Prychodiko
,
M.
, 2003, “
Development of Outlook of Gas-Water Jet Energy-Propulsion Complexes for High Speed Water Vehicles
,”
Fifth International Symposium on Cavitation (CAV2003)
, Osaka, Japan, Paper No. CAV03-OS-7-021.
13.
Mor
,
M.
, and
Gany
,
A.
, 2004, “
Analysis of Two-Phase Homogeneous Bubbly Flows Including Friction and Mass Addition
,”
ASME Trans. J. Fluids Eng.
0098-2202,
126
, pp.
102
–
109
.
Crossref
Search ADS
 
14.
Mor
,
M.
, and
Gany
,
A.
, 2007, “
Performance Mapping of Bubbly Water Ramjet
,”
Int. J. Marit. Eng.
1479-8751,
149
, pp.
45
–
50
.
15.
Schell
,
C. J.
, Jr., and
Ornoff
,
H.
, 1965, “
Hydro-Pneumatic Ramjet
,” U.S. Patent No. 3,171,379.
16.
Brown
,
A. E.
, and
Stern
,
H.
, 1966, “
Propulsor
,” U.S. Patent No. 3,265,027.
17.
Scott-Scott
,
J. L.
, 1982, “
Marine Propulsion
,” U.S. Patent No. 4,343,611.
18.
Varshay
,
H.
, and
Gany
,
A.
, 1997, “
Underwater Two-Phase Ramjet Engine
,” U.S. Patent No. 5,692,371.
19.
Burns
,
A. R.
, 2003, “
Propulsion System
,” U.S. Patent No. 6,662,549.
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