Pressure-equalizing film is a slice of air film generated through exhausting and attached to the vehicle's exterior with nearly uniform inner pressure. Similar to ventilated cavity in composition, but of interest, here is the weakening of pitching moment and environment disturbance that the film offers, the film's forming speed and covering range upon vehicle determine the improvement effect of vehicle's trajectory stability as it emerges from water. This paper established a numerical approach to investigate the effect of single and double rows of venting holes on the evaluation of air film along vehicle's exterior, at the same time its influence on the trajectory stability of vehicle with three degrees-of-freedom (3DOF) motion is also analyzed. Results indicate that reverse flow forms between row-to-row spacing when exhausting with two rows of holes, which enhances the exhausting process with the film's size enlarged and axial length extended, meanwhile it brings about more complex vortices structure near venting holes compared to the single-row hole case. As for the 3DOF cases, the pressure difference between vehicle's front and back sides is dramatically reduced attributing to the existence of attached air film, consequently the rotation of vehicle is weaken, leaving a better attitude to vehicle after it piercing water surface. Besides, the rapid formation of air film in double-row hole cases is advantage for the timely inhibiting of vehicle's pitching motion compared to the single-row hole cases, and their weaker stagnation high pressure near film's closure region is also good for the reduction of vehicle's lateral load.

References

References
1.
Quan
,
X. B.
,
Yan
,
G. J.
,
Li
,
Y.
,
Kong
,
D. C.
, and
Li
,
M.
,
2014
, “
Three-Dimensional Numerical Study on the Evolution Process of Tail Bubble of Underwater Vehicle Vertical Launching
,”
J. Ship Mech.
,
18
(
7
), pp.
739
745
.
2.
Liu
,
Y. B.
,
Feng
,
Y. M.
, and
Liu
,
W. W.
,
2012
, “
Dynamic Response Calculations of the Whole Missile When Considering the Local Nonlinearities of the Cabin
,”
Missiles Space Veh.
,
318
(
2
), pp.
30
34
.
3.
Ding
,
Y. C.
, and
Wang
,
B. S.
,
2011
, “
Study on the Thrust Vector Control Trajectory of Underwater Vertical Launching Missile
,”
J. Ship Mech.
,
5
(
1–2
), pp.
87
94
.
4.
Wang
,
Z. Y.
,
Cheng
,
S. H.
,
Yu
,
H. T.
,
Wang
,
G. J.
, and
Pei
,
J. L.
,
2016
, “
Stability Studies of Trajectory of Launched Vehicles Under Deep Water
,”
Ordnance Ind. Autom.
,
35
(
6
), pp.
1
5
.
5.
Li
,
J.
,
Lu
,
C. J.
,
Chen
,
X.
, and
Cao
,
J. Y.
,
2014
, “
Analysis on Influence of Attached Cavity on the Trajectory of Submarine Launched Missile
,”
J. Ballist.
,
26
(
3
), pp.
54
58
.
6.
Zhang
,
X. S.
, and
Wang
,
C.
,
2015
, “
Research on Underwater Vehicle Based on Multiphase Flow Control
,”
International Conference on Energy, Materials and Manufacturing Engineering (EMME)
, Kuala Lumpur, Malaysia, Oct. 15–16, Paper No. 03004.
7.
Chen
,
F.
,
Ma
,
G. H.
,
Yu
,
J. Y.
, and
Jiang
,
S.
,
2016
, “
Effect of Exhaust Angle on Evolutionary and Flow Characteristics of Pressure-Equalizing Film on Surface of Underwater Vehicle
,”
J. Ship Mech.
,
20
(
12
), pp.
1495
1512
.
8.
New
,
T. H.
,
Lim
,
T. T.
, and
Luo
,
S. C.
,
2003
, “
Elliptic Jets in Cross-Flow
,”
J. Fluid Mech.
,
494
, pp.
119
140
.
9.
Barata
,
J. M. M.
, and
Durao
,
D. F. G.
,
2004
, “
Laser-Doppler Measurements of Impinging Jet Flows Through a Crossflow
,”
Exp. Fluids
,
36
(
2004
), pp.
665
674
.
10.
Mahesh
,
K.
,
2013
, “
The Interaction of Jets With Crossflow
,”
Annu. Rev. Fluid Mech.
,
45
(
1
), pp.
379
407
.
11.
Sau
,
A.
,
Sheu
,
T. W. H.
,
Hwang
,
R. R.
, and
Yang
,
W. C.
,
2004
, “
Three-Dimensional Simulation of Square Jets in Cross-Flow
,”
Phys. Rev. E
,
69
(
6
), p.
066302
.
12.
Jiang
,
G. Q.
,
Ren
,
X. W.
, and
Li
,
W.
,
2010
, “
Numerical Simulation of Vorticity Dynamics for Turbulent Jet in Crossflow
,”
Adv. Water Sci.
,
21
(
3
), pp.
307
314
.
13.
Brandner
,
P. A.
,
Pearce
,
B. W.
, and
Graaf
,
K. L. D.
,
2015
, “
Cavitation about a Jet in Crossflow
,”
J. Fluid Mech.
,
768
, pp.
141
174
.
14.
Yu
,
X. X.
,
Huang
,
C. G.
,
Du
,
T. Z.
,
Liao
,
L. J.
,
Wu
,
X. C.
,
Zheng
,
Z.
, and
Wang
,
Y. W.
,
2014
, “
Study of Characteristics of Cloud Cavity Around Axisymmetric Projectile by Large Eddy Simulation
,”
ASME J. Fluids Eng.
,
136
(
5
), p.
051303
.
15.
Zhang
,
X. W.
,
Zhang
,
J. Z.
,
Wang
,
C.
,
Wei
,
Y. J.
,
Yu
,
K. P.
, and
Wei
,
X. B.
,
2007
, “
Experimental Research on Ventilated Cavitation and Its Stability
,”
J. Harbin Eng. Univ.
,
28
(
4
), pp.
381
387
.
16.
Yang
,
W. G.
,
Zhang
,
Y. W.
,
Deng
,
F.
,
Yuan
,
X. L.
,
Fan
,
H.
, and
Kan
,
L.
,
2007
, “
Exploring Experimentally Effect of Gas Entrainment Rate on Geometrical Shape of Supercavity
,”
J. Northwest. Polytech. Univ.
,
25
(
3
), pp.
358
362
.
17.
Zhang
,
J. H.
,
Zhang
,
Y. W.
, and
Li
,
Y. T.
,
2011
, “
Experimental Study of Ventilation Supercavitation Generation and Maintenance Produced by Underwater Vehicle
,”
J. Exp. Mech.
,
26
(
6
), pp.
715
720
.
18.
Wang
,
Y. W.
,
Huang
,
C. G.
,
Fang
,
X.
,
Yu
,
X. X.
,
Wu
,
X. C.
, and
Du
,
T. Z.
,
2016
, “
Cloud Cavitation Flow Over a Submerged Axisymmetric Projectile and Comparison Between Two-Dimensional RANS and Three-Dimensional Large-Eddy Simulation Methods
,”
ASME J. Fluids Eng.
,
138
(
6
), p.
061102
.
19.
Zhang
,
X. S.
,
Wang
,
C.
, and
Wekesa
,
D. W.
,
2017
, “
Numerical and Experimental Study of Pressure-Wave Formation Around an Under-Water Ventilated Vehicle
,”
Eur. J. Mech. B
,
65
, pp.
440
449
.
20.
Wang
,
Y. W.
,
Wu
,
X. C.
,
Huang
,
C. G.
, and
Wu
,
X. Q.
,
2016
, “
Unsteady Characteristics of Cloud Cavitating Flow Near the Free Surface Around an Axisymmetric Projectile
,”
Int. J. Multiphase Flow
,
85
, pp.
48
56
.
21.
Chen
,
C. Q.
,
Cao
,
W.
,
Wang
,
C.
,
Ren
,
H. X.
, and
Sun
,
J.
,
2014
, “
Simulation of the Underwater Trajectory of a Submarine Launched Vehicle Considering Cavitation Conditions
,”
Eng. Mech.
,
31
(
10
), pp.
242
247
.
22.
Ma
,
G. H.
,
Chen
,
F.
,
Yu
,
J. Y.
, and
Liu
,
H. P.
,
2018
, “
Flow Mechanism and Characteristics of Pressure-Equalizing Film Along the Surface of a Moving Underwater Vehicle
,”
ASME J. Fluids Eng.
,
140
(
4
), p.
041103
.
23.
Wang
,
G. Y.
,
Cui
,
Z. Y.
,
Huang
,
B.
, and
Gao
,
D. M.
,
2017
, “
Analysis on Gas-Liquid Two-Phase Flows Characteristics Around a Plane
,”
Trans. Beijing Inst. Technol.
,
31
(
1
), pp.
42
45
.
24.
Sakai
,
E.
,
Takahashi
,
T.
, and
Watanabe
,
H.
,
2014
, “
Large-Eddy Simulation of an Inclined Round Jet Issuing Into a Crossflow
,”
Int. J. Heat Mass Transfer
,
69
, pp.
300
311
.
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