An experimental study of the turbulent near wake of a rotating circular cylinder was made at a Reynolds number of 2000 for velocity ratios, λ between 0 and 2.7. Particle image velocimetry data are analyzed to study the effects of rotation on the flow structures behind the cylinder. The results indicate that the rotation of the cylinder causes significant changes in the vortex formation. Kármán vortex shedding pattern of alternating vortices gives rise to strong periodic fluctuations of a vortex street for λ < 2.0. Alternate vortex shedding is weak and close to being suppressed at λ = 2.0 resulting a distorted street with vortices of alternating sense subsequently being found on opposite sides. Only part of the circulation is shed due to the interference in the separation point, mixing in the base region, re-attachment, and vortex cut-off phenomenon. Alternating vortex shedding pattern diminishes and completely disappears when the velocity ratio is 2.7. The shed vortices are insignificant in size and forming a single line of vortex street. It is clear that flow asymmetries will deteriorate vortex shedding, and when the asymmetries are large enough, total inhibition of a periodic street occurs.
[1] Barnes, F.H. (2000). Vortex shedding in the wake of a rotating circular
cylinder at low Reynolds number, J. Physics, Vol. 33, pp. 141.
[2] Massons, J., Ruiz, X. and Diaz, F. (1989). Image processing of the near
wakes of stationary and rotating cylinders, Journal of Fluid Mechanics,
Vol. 204, pp. 167.
[3] Tanaka, H. and Nagano, S. (1973). Study of flow around a rotating
circular cylinder, Bull. JSME, Vol. 16, pp. 234.
[4] Swanson, W.M. (1961). The Magnus effect: A summary of
investigations to date, Journal of Basic Engineering, Vol. 83, pp. 461.
[5] Diaz, F., Gavalda, J., Kawall, J.G., Keffer, J.F. and Giralt, F. (1983).
Vortex shedding from a spinning cylinder, Physics of Fluids, Vol. 26,
pp. 3454.
[6] Badr, H.M., Coutanceau, M., Dennis, S.C.R. and Menard, C. (1990).
Unsteady flow past a rotating circular cylinder at Reynolds number 103
and 104, Journal of Fluid Mechanics, Vol. 220, pp. 459.
[7] Chang, C.C. and Chern, R.L. (1991). Vortex shedding from an
impulsively started rotating and translating circular cylinder, Journal of
Fluid Mechanics, Vol. 233, pp. 265.
[8] Chew, Y.T., Cheng, M. and Luo, S.C. (1995). A numerical study of
flow past a rotating circular cylinder using a hybrid vortex scheme,
Journal of Fluid Mechanics,Vol. 299, pp. 35.
[9] Dol, S.S., Kopp, G.A. and Martinuzzi, R.J. (2008).The suppression of
periodic vortex shedding from a rotating circular cylinder, Journal of
Wind Engineering and Industrial Aerodynamics,96, pp.1164–1184
[10] West, G.S. and Apelt, C.J. (1982). The effects of tunnel blockage and
aspect ratio on the mean flow past a circular cylinder with Reynolds
number between 104 and 105, Journal of Fluid Mechanics, Vol. 114, pp.
361.
[11] Laneville, A. (1990). Turbulence and blockage effects on two
dimensional rectangular cylinders, Journal of Wind Engineering and
Industrial Aerodynamics,Vol. 33, pp. 11.
[12] Coleman, H.W. and Steele, W.G. (1989). Experimental Uncertainty
Analysis for Engineers, Wiley, New York.
[13] Roshko, A. (1954). On the drag and shedding frequency of twodimensional
bluff bodies, NACA TN No. 3169.
[14] Zdravkovich, M.M. (1997). Flow around circular cylinders: a
comprehensive guide through flow phenomena, experiments,
applications, mathematical models, and computer simulations, Vol. 1:
Fundamentals, Oxford University Press, Oxford, UK.
[15] Zdravkovich, M.M. (2003). Flow around circular cylinders: a
comprehensive guide through flow phenomena, experiments,
applications, mathematical models, and computer simulations, Vol. 2:
Applications, Oxford University Press, Oxford, UK.
[16] Dol, S.S. (2004). The suppression of periodic vortex shedding from a
rotating circular cylinder. M.E.Sc. Thesis. Western Ontario University,
Ontario, Canada.
[17] Bailey, S.C.C., Kopp, G.A. and Martinuzzi, R.J. (2003). Vortex
shedding from a square cylinder near a wall, Journal of Turbulence,
Vol. 3, pp. 1.
[18] Saffman, P.G. and Schatzman, J.C. (1981). An inviscid model for the
vortex-street wake, Journal of Fluid Mechanics, Vol. 122, pp. 467.
[1] Barnes, F.H. (2000). Vortex shedding in the wake of a rotating circular
cylinder at low Reynolds number, J. Physics, Vol. 33, pp. 141.
[2] Massons, J., Ruiz, X. and Diaz, F. (1989). Image processing of the near
wakes of stationary and rotating cylinders, Journal of Fluid Mechanics,
Vol. 204, pp. 167.
[3] Tanaka, H. and Nagano, S. (1973). Study of flow around a rotating
circular cylinder, Bull. JSME, Vol. 16, pp. 234.
[4] Swanson, W.M. (1961). The Magnus effect: A summary of
investigations to date, Journal of Basic Engineering, Vol. 83, pp. 461.
[5] Diaz, F., Gavalda, J., Kawall, J.G., Keffer, J.F. and Giralt, F. (1983).
Vortex shedding from a spinning cylinder, Physics of Fluids, Vol. 26,
pp. 3454.
[6] Badr, H.M., Coutanceau, M., Dennis, S.C.R. and Menard, C. (1990).
Unsteady flow past a rotating circular cylinder at Reynolds number 103
and 104, Journal of Fluid Mechanics, Vol. 220, pp. 459.
[7] Chang, C.C. and Chern, R.L. (1991). Vortex shedding from an
impulsively started rotating and translating circular cylinder, Journal of
Fluid Mechanics, Vol. 233, pp. 265.
[8] Chew, Y.T., Cheng, M. and Luo, S.C. (1995). A numerical study of
flow past a rotating circular cylinder using a hybrid vortex scheme,
Journal of Fluid Mechanics,Vol. 299, pp. 35.
[9] Dol, S.S., Kopp, G.A. and Martinuzzi, R.J. (2008).The suppression of
periodic vortex shedding from a rotating circular cylinder, Journal of
Wind Engineering and Industrial Aerodynamics,96, pp.1164–1184
[10] West, G.S. and Apelt, C.J. (1982). The effects of tunnel blockage and
aspect ratio on the mean flow past a circular cylinder with Reynolds
number between 104 and 105, Journal of Fluid Mechanics, Vol. 114, pp.
361.
[11] Laneville, A. (1990). Turbulence and blockage effects on two
dimensional rectangular cylinders, Journal of Wind Engineering and
Industrial Aerodynamics,Vol. 33, pp. 11.
[12] Coleman, H.W. and Steele, W.G. (1989). Experimental Uncertainty
Analysis for Engineers, Wiley, New York.
[13] Roshko, A. (1954). On the drag and shedding frequency of twodimensional
bluff bodies, NACA TN No. 3169.
[14] Zdravkovich, M.M. (1997). Flow around circular cylinders: a
comprehensive guide through flow phenomena, experiments,
applications, mathematical models, and computer simulations, Vol. 1:
Fundamentals, Oxford University Press, Oxford, UK.
[15] Zdravkovich, M.M. (2003). Flow around circular cylinders: a
comprehensive guide through flow phenomena, experiments,
applications, mathematical models, and computer simulations, Vol. 2:
Applications, Oxford University Press, Oxford, UK.
[16] Dol, S.S. (2004). The suppression of periodic vortex shedding from a
rotating circular cylinder. M.E.Sc. Thesis. Western Ontario University,
Ontario, Canada.
[17] Bailey, S.C.C., Kopp, G.A. and Martinuzzi, R.J. (2003). Vortex
shedding from a square cylinder near a wall, Journal of Turbulence,
Vol. 3, pp. 1.
[18] Saffman, P.G. and Schatzman, J.C. (1981). An inviscid model for the
vortex-street wake, Journal of Fluid Mechanics, Vol. 122, pp. 467.
@article{"International Journal of Mechanical, Industrial and Aerospace Sciences:65436", author = "Sharul S. Dol", title = "Weakened Vortex Shedding from a Rotating Cylinder", abstract = "An experimental study of the turbulent near wake of a rotating circular cylinder was made at a Reynolds number of 2000 for velocity ratios, λ between 0 and 2.7. Particle image velocimetry data are analyzed to study the effects of rotation on the flow structures behind the cylinder. The results indicate that the rotation of the cylinder causes significant changes in the vortex formation. Kármán vortex shedding pattern of alternating vortices gives rise to strong periodic fluctuations of a vortex street for λ < 2.0. Alternate vortex shedding is weak and close to being suppressed at λ = 2.0 resulting a distorted street with vortices of alternating sense subsequently being found on opposite sides. Only part of the circulation is shed due to the interference in the separation point, mixing in the base region, re-attachment, and vortex cut-off phenomenon. Alternating vortex shedding pattern diminishes and completely disappears when the velocity ratio is 2.7. The shed vortices are insignificant in size and forming a single line of vortex street. It is clear that flow asymmetries will deteriorate vortex shedding, and when the asymmetries are large enough, total inhibition of a periodic street occurs.
", keywords = "Circulation, particle image velocimetry, rotating circular cylinder, smoke-wire flow visualization, Strouhal number, vortex shedding, vortex street.", volume = "7", number = "10", pages = "2029-8", }
