Abstract

Nitrous oxide is a suitable propellant for rocket engines and has been widely used in various countries, given its high saturated vapor pressure, which enables self-pressurization. Because nitrous oxide is in a state of vapor–liquid equilibrium in tanks, it is easy to form a gas–liquid two-phase flow by cavitation in feed line. Since accurately estimating the performance of rocket engines requires evaluating the characteristics of propellant flows, tests reported in this paper were conducted using hybrid rocket engines under three conditions: cold flow test, hot firing test at low back pressure, and hot firing test at high back pressure. With consideration to the subcooling degrees, nitrous oxide may be in an unsteady superheated state in the upstream flow of the injector. In a comparison of the pressure ratios between the injector in each test condition, it is observed that a critical two-phase flow was formed in the injector in the cold flow test and in the low backpressure firing test. In the high backpressure hot firing test, the injector flow may be choked, but the large oscillations were observed in chamber pressure and thrust. According to the FFT analysis results, these oscillations were caused by chugging and acoustic oscillation. In light of these experimental results, it is suggested that when the chamber pressure fluctuates due to combustion instability such as chugging and acoustic oscillation, it may affect the injector flow characteristics and the critical two-phase flow.

References

References
1.
Zakirov
,
V.
,
Sweeting
,
M.
,
Lawrence
,
T.
, and
Sellers
,
J.
,
2001
, “
Nitrous Oxide as a Rocket Propellant
,”
Acta Astronaut.
,
48
(
5–12
), pp.
353
362
.10.1016/S0094-5765(01)00047-9
2.
Tokudome
,
S.
,
Yagishita
,
T.
,
Habu
,
H.
,
Shimada
,
T.
, and
Daimo
,
Y.
,
2007
, “
Experimental Study of an N2O/Ethanol Propulsion System
,”
AIAA Paper No. 2007-5464
. 10.2514/6.2007-5464
3.
Chen
,
Y.
, and
Wu
,
B.
,
2018
, “
Development of a Small Launch Vehicle With Hybrid Rocket Propulsion
,”
AIAA Paper No. 2018-4835
.10.2514/6.2018-4835
4.
Kobald
,
M.
,
Fischer
,
U.
,
Tomilin
,
K.
,
Petrarolo
,
A.
, and
Schmierer
,
C.
,
2018
, “
Hybrid Experimental Rocket Stuttgart: A Low-Cost Technology Demonstrator
,”
AIAA J. Spacecr. Rockets
,
55
(
2
), pp.
484
500
.10.2514/1.A34035
5.
Chandler
,
A. A.
,
Cantwell
,
J. B.
,
Hubbard
,
S. G.
, and
Karabeyoglu
,
A.
,
2011
, “
Feasibility of Single Port Hybrid Propulsion System for a Mars Ascent Vehicle
,”
Acta Astronaut.
,
69
(
11–12
), pp.
1066
1072
.10.1016/j.actaastro.2011.07.004
6.
Chiaverini
,
M. J.
, and
Kou
,
K. K.
,
2007
,
Fundamentals of Hybrid Rocket Combustion and Propulsion
,
American Institute of Aeronautics and Astronautics
,
Reston, VA
.
7.
Karabeyoglu
,
A.
,
Dyer
,
J.
,
Stevens
,
J.
, and
Cantwell
,
B.
,
2008
, “
Modeling of N2O Decomposition Events
,”
AIAA Paper No. 2008-4933
.10.2514/6.2008-4933
8.
Whitmore
,
S. A.
, and
Chandler
,
S. N.
,
2010
, “
Engineering Model for Self-Pressurizing Saturated-N2O-Propellant Feed Systems
,”
AIAA J. Propul. Power
,
26
(
4
), pp.
706
714
.10.2514/1.47131
9.
Zilliac
,
G.
, and
Karabeyoglu
,
A.
,
2005
, “
Modeling of Propellant Tank Pressurization
,”
AIAA Paper No. 2005-3549
.10.2514/6.2005-3549
10.
Casalino
,
L.
, and
Pastrone
,
D.
,
2008
, “
Optimal Design of Hybrid Rocket Motors for Microgravity Platform
,”
AIAA J. Propul. Power
,
24
(
3
), pp.
491
498
.10.2514/1.30548
11.
Nakata
,
D.
,
Yasuda
,
K.
,
Okada
,
K.
,
Higashino
,
K.
, and
Watanabe
,
R.
,
2018
, “
N2O Flow History Prediction in an Oxidizer Feed Line of Hybrid Rockets
,”
Trans. Jpn. Soc. Aeronaut. Space Sci., Aerosp. Technol. Jpn.
,
16
(
1
), pp.
81
87
.10.2322/tastj.16.81
12.
Zimmerman
,
J. E.
, and
Cantwell
,
B.
,
2015
, “
Parametric Visualization Study of Self-Pressurizing Propellant Tank Dynamics
,”
AIAA Paper No. 2015-3829
. 10.1115/2015-3829
13.
Nurick
,
W. H.
,
1976
, “
Orifice Cavitation and Its Effect on Spray Mixing
,”
ASME J. Fluids Eng.
,
98
(
4
), pp.
681
687
.10.1115/1.3448452
14.
Nurick
,
W. H.
,
Ohanian
,
T.
,
Talley
,
D. G.
, and
Strakey
,
P. A.
,
2008
, “
The Impact of Manifold-to-Orifice Turning Angle on Sharp-Edge Orifice Flow Characteristics in Both Cavitation and Noncavitation Turbulent Flow Regimes
,”
ASME J. Fluids Eng.
,
130
(
12
), p.
121102
.10.1115/1.2978999
15.
Nurick
,
W. H.
,
Ohanian
,
T.
,
Talley
,
D. G.
, and
Strakey
,
P. A.
,
2009
, “
Impact of Orifice Length/Diameter Ratio on 90 Deg Sharp-Edge Orifice Flow With Manifold Passage Cross Flow
,”
ASME J. Fluids Eng.
,
131
(
8
), p.
081103
.10.1115/1.3155959
16.
Rohloff
,
T. J.
, and
Catton
,
I.
,
1996
, “
Low Pressure Differential Discharge Characteristics of Saturated Liquids Passing Through Orifices
,”
ASME J. Fluids Eng.
,
118
(
3
), pp.
520
525
.10.1115/1.2817789
17.
Ebrahimi
,
B.
,
He
,
G.
,
Tang
,
Y.
,
Franchek
,
M.
,
Liu
,
D.
,
Pickett
,
J.
,
Springett
,
F.
, and
Franklin
,
D.
,
2017
, “
Characterization of High-Pressure Cavitating Flow Through a Thick Orifice Plate in a Pipe of Constant Cross Section
,”
Int. J. Therm. Sci.
,
114
, pp.
229
240
.10.1016/j.ijthermalsci.2017.01.001
18.
Waxman
,
B. S.
,
Zimmerman
,
J. E.
, and
Cantwell
,
B. J.
,
2013
, “
Mass Flow Rate and Isolation Characteristics of Injectors for Use With Self-Pressurizing Oxidizers in Hybrid Rockets
,”
AIAA Paper No. 2013-3636
.10.1115/2013-3636
19.
NIST
,
2018
, “
NIST Database
,”
NIST
,
Gaithersburg, MD
, accessed May 5, 2020, https://webbook.nist.gov/chemistry/
20.
Sutton
,
G. P.
, and
Biblarz
,
O.
,
2016
,
Rocket Propulsion Elements
, 9th ed.,
Wiley
,
Hoboken, NJ
.
21.
Abernethy
,
R. B.
,
Benedict
,
R. P.
, and
Dowdell
,
R. B.
,
1985
, “
ASME Measurement Uncertainty
,”
ASME J. Fluids Eng.
,
107
(
2
), pp.
161
164
.10.1115/1.3242450
22.
Harrje
,
D. T.
,
1972
, “
Liquid Propellant Rocket Combustion Instability
,”
NASA Headquarters
,
Washington, DC
, Report No. NASA SP-194.
23.
Gordon
,
S.
, and
McBride
,
B. J.
,
1994
, “
Computer Program for Calculation of Complex Chemical Equilibrium Compositions and Applications I. Analysis
,”
NASA Headquarters
,
Washington, DC
, Report No. NASA RP-1311.
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