Location of Vortex Formation Threshold at Suction Inlets near Ground Planes – Ascending and Descending Conditions
Vortices can develop in intakes of turbojet and turbo
fan aero engines during high power operation in the vicinity of solid
surfaces. These vortices can cause catastrophic damage to the engine.
The factors determining the formation of the vortex include both
geometric dimensions as well as flow parameters. It was shown that
the threshold at which the vortex forms or disappears is also
dependent on the initial flow condition (i.e. whether a vortex forms
after stabilised non vortex flow or vice-versa). A computational fluid
dynamics study was conducted to determine the difference in
thresholds between the two conditions. This is the first reported
numerical investigation of the “memory effect". The numerical
results reproduce the phenomenon reported in previous experimental
studies and additional factors, which had not been previously studied,
were investigated. They are the rate at which ambient velocity
changes and the initial value of ambient velocity. The former was
found to cause a shift in the threshold but not the later. It was also
found that the varying condition thresholds are not symmetrical about
the neutral threshold. The vortex to no vortex threshold lie slightly
further away from the neutral threshold compared to the no vortex to
vortex threshold. The results suggests that experimental investigation
of vortex formation threshold performed either in vortex to no vortex
conditions, or vice versa, solely may introduce mis-predictions
greater than 10%.
[1] W.H. Ho, H. Dumbleton and M. Jermy, "Effect of Upstream Velocity
Gradient on the Formation of Sink Vortices in a Jet Engine Test Cell",
IMECS 2008 Proceedings, pp 1767 - 1772, 2008.
[2] A. Karlsson and L. Fuchs, "Time evolution of the vortex between an air
inlet and the ground". AIAA paper 2000-0990, 2000.
[3] A. Secareanu, D. Morioanu, A. Karlsson and L. Fuchs, "Experimental
and numerical study of ground vortex interaction in an air-intake, AIAA
paper 2005-1206, 2005.
[4] A. Gulia, P. Laskaridis, K.W. Ramsden and P. Pilidis, "A preliminary
investigation of thrust measurement correction in an enclosed engine test
facility, AIAA paper 2005-1128, 2005.
[5] S. Zantopp, D. Macmanus and J. Murphy, "Computational and
experimental study of intake ground vortices", The Aeronautical Journal
Vol. 114 No. 1162, 2010.
[6] M. Jermy and W.H. Ho, "Location of the vortex formation threshold at
suction inlets near ground planes by computational fluid dynamics
simulation", Proceedings of the I Mech E Part G Journal of Aerospace
Engineering Vol. 222 No. 3, pp. 393-402, 2008.
[7] W.H. Ho, M. Jermy and H. Dumbleton, "Formation of Sink Vortices in
a Jet Engine Test Cell", Engineering Letters 16:3, pp. 406-411, 2008.
[8] W.H. Ho and M. Jermy, "Formation and Ingestion of Vortices into Jet
Engines during operation", IAENG TRANSACTIONS ON
ENGINEERING TECHNOLOGIES VOL. 1 - Special Editions of the
International MultiConference of Engineers and Computer Scientists
2008, pp 132 - 143, 2008.
[9] W.H. Ho and M. Jermy, "Validated CFD simulations of vortex
formation in jet engine test cells", 16th Australasian Fluid Mechanics
Conference Proceedings, pp. 1102-1107, 2007.
[10] A. Nakayama and J.R. Jones, "Vortex formation in let flow near a wall",
AIAA paper 96-0803, 1996.
[11] D.E. Glenny, "Ingestion of debris into intakes by vortex action,
Aeronautical Research Council CP No. 1114, 1970.
[12] W. Liu, E.M. Greitzer and C.S. Tan, "Surface static pressure in an inlet
vortex flow field", ASME J. Engineering Gas Turbines Power 107, pp.
387-393, 1985.
[13] S.O. Ridder and I. Samuelsson, "An experimental study of strength and
existence of domain of ground-to-air inlet vortices by ground board
static pressure measurements, Stockholm Royal Institute of Technology,
KTH AERO TN 62, 1982.
[14] W.H. Ho and M. Jermy, "Effect of Turbulence Intensity on Vortex
Formation Threshold in a Jet Engine Test Cell", 25th European
Conference on Modelling and Simulation (ECMS) Proceedings, 2011.
[15] F. De Siervi, H.C. Viguier, E.M. Greitzer and C.S. Tan, "Mechanisms of
inlet vortex formation", J. Fluid Mech. 124, pp. 173-207, 1982.
[16] J.P. Murphy and D.G. MacManus, "Intake Ground Vortex Prediction
Methods", Journal of Aircraft Vol 48 No. 1, 2011.
[1] W.H. Ho, H. Dumbleton and M. Jermy, "Effect of Upstream Velocity
Gradient on the Formation of Sink Vortices in a Jet Engine Test Cell",
IMECS 2008 Proceedings, pp 1767 - 1772, 2008.
[2] A. Karlsson and L. Fuchs, "Time evolution of the vortex between an air
inlet and the ground". AIAA paper 2000-0990, 2000.
[3] A. Secareanu, D. Morioanu, A. Karlsson and L. Fuchs, "Experimental
and numerical study of ground vortex interaction in an air-intake, AIAA
paper 2005-1206, 2005.
[4] A. Gulia, P. Laskaridis, K.W. Ramsden and P. Pilidis, "A preliminary
investigation of thrust measurement correction in an enclosed engine test
facility, AIAA paper 2005-1128, 2005.
[5] S. Zantopp, D. Macmanus and J. Murphy, "Computational and
experimental study of intake ground vortices", The Aeronautical Journal
Vol. 114 No. 1162, 2010.
[6] M. Jermy and W.H. Ho, "Location of the vortex formation threshold at
suction inlets near ground planes by computational fluid dynamics
simulation", Proceedings of the I Mech E Part G Journal of Aerospace
Engineering Vol. 222 No. 3, pp. 393-402, 2008.
[7] W.H. Ho, M. Jermy and H. Dumbleton, "Formation of Sink Vortices in
a Jet Engine Test Cell", Engineering Letters 16:3, pp. 406-411, 2008.
[8] W.H. Ho and M. Jermy, "Formation and Ingestion of Vortices into Jet
Engines during operation", IAENG TRANSACTIONS ON
ENGINEERING TECHNOLOGIES VOL. 1 - Special Editions of the
International MultiConference of Engineers and Computer Scientists
2008, pp 132 - 143, 2008.
[9] W.H. Ho and M. Jermy, "Validated CFD simulations of vortex
formation in jet engine test cells", 16th Australasian Fluid Mechanics
Conference Proceedings, pp. 1102-1107, 2007.
[10] A. Nakayama and J.R. Jones, "Vortex formation in let flow near a wall",
AIAA paper 96-0803, 1996.
[11] D.E. Glenny, "Ingestion of debris into intakes by vortex action,
Aeronautical Research Council CP No. 1114, 1970.
[12] W. Liu, E.M. Greitzer and C.S. Tan, "Surface static pressure in an inlet
vortex flow field", ASME J. Engineering Gas Turbines Power 107, pp.
387-393, 1985.
[13] S.O. Ridder and I. Samuelsson, "An experimental study of strength and
existence of domain of ground-to-air inlet vortices by ground board
static pressure measurements, Stockholm Royal Institute of Technology,
KTH AERO TN 62, 1982.
[14] W.H. Ho and M. Jermy, "Effect of Turbulence Intensity on Vortex
Formation Threshold in a Jet Engine Test Cell", 25th European
Conference on Modelling and Simulation (ECMS) Proceedings, 2011.
[15] F. De Siervi, H.C. Viguier, E.M. Greitzer and C.S. Tan, "Mechanisms of
inlet vortex formation", J. Fluid Mech. 124, pp. 173-207, 1982.
[16] J.P. Murphy and D.G. MacManus, "Intake Ground Vortex Prediction
Methods", Journal of Aircraft Vol 48 No. 1, 2011.
@article{"International Journal of Mechanical, Industrial and Aerospace Sciences:64804", author = "Wei Hua Ho", title = "Location of Vortex Formation Threshold at Suction Inlets near Ground Planes – Ascending and Descending Conditions", abstract = "Vortices can develop in intakes of turbojet and turbo
fan aero engines during high power operation in the vicinity of solid
surfaces. These vortices can cause catastrophic damage to the engine.
The factors determining the formation of the vortex include both
geometric dimensions as well as flow parameters. It was shown that
the threshold at which the vortex forms or disappears is also
dependent on the initial flow condition (i.e. whether a vortex forms
after stabilised non vortex flow or vice-versa). A computational fluid
dynamics study was conducted to determine the difference in
thresholds between the two conditions. This is the first reported
numerical investigation of the “memory effect". The numerical
results reproduce the phenomenon reported in previous experimental
studies and additional factors, which had not been previously studied,
were investigated. They are the rate at which ambient velocity
changes and the initial value of ambient velocity. The former was
found to cause a shift in the threshold but not the later. It was also
found that the varying condition thresholds are not symmetrical about
the neutral threshold. The vortex to no vortex threshold lie slightly
further away from the neutral threshold compared to the no vortex to
vortex threshold. The results suggests that experimental investigation
of vortex formation threshold performed either in vortex to no vortex
conditions, or vice versa, solely may introduce mis-predictions
greater than 10%.", keywords = "Jet Engine Test Cell, Unsteady flow, Inlet Vortex", volume = "5", number = "11", pages = "2536-8", }