Abstract
The paper summarizes results of an experimental study of the flow through an axisymmetric, ring-type constriction of finite length located in a pipe. The mean velocity and mean values of the fluctuating axial and radial velocity components were measured together with the azimuthal fluctuations and Reynolds stresses. Particular attention was given to the near wall region. Two Reynolds numbers were investigated. Using a definition of the Reynolds number based on the ring diameter and the maximum centreline velocity, their values were 1.3 × 104 and 2.2 × 104, lying respectively marginally and fully in the turbulent regime of the flow.
Reattachment lengths were measured for Reynolds numbers in the range of 1 × 102 to 1.1 × 105. Flow visualization revealed the presence of well-ordered vortex rings for Reynolds numbers up to 2000.
Detailed velocity measurements were carried out and revealed the existence of three recirculating zones; one extending upstream of the obstacle, the main one extending from 1.6 to 11 obstacle heights (H) downstream of the obstacle (depending on the value of Re) and a third, much smaller reverse flow region, in the vicinity of the obstacle and within the main recirculation zone. The low levels of turbulence intensity prevailing at 16 H upstream of the obstacle were not recovered at 28 H downstream.
A similarity relationship for Re > 1000 is found by the analysis of the centreline properties. This similarity shows a surprising independence of Reynolds numbers, inlet flow profiles and outside geometric configurations and an interesting intimate relationship between centreline properties and those of the near wall. The axial symmetric ‘free jet phenomena’ in the centreline region of the expansion pipe flow is quantitatively revealed for the first time.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Back, L. H., Roschke, E. J. (1972): Shear layer regimes and wave instabilities and reattachment lengths downstream of an abrupt circular sudden expansion. ASME, J. Appl. Mech. 94, 677
Charturvedi, M. C. (1963): Flow characteristics of axisymmetric expansions. J. Hydraul. Div. p. 61
Durao, D. F. G., Firmino, F. C. (1983): “Velocity Field Around a Disk,” in Proceedings of the Fourth Symposium on Turbulent Shear Flows, Karlsruhe, FRG, paper no. 1919
Durao, D. F. G., Heitor, M., Pereira, J. C. F. (1986): “A Laser Anemometry Study of Separated Flow Around a Squared Obstacle,” in Proceedings of the 3rd Int. Symposium on Applications of Laser Anemometry to Fluid Mechanics, Lisbon, Portugal
Durst, F., Loy, T. (1985): Investigations of laminar flow in a pipe with sudden contraction of cross sectional area. Comp. Fluids 13/1, 15
Khezzar, L. (1985): An experimental study of flows through round sudden expansions. Imperial College, Report No. FS/85/14, London
Krall, K. M., Sparrow, E. M. (1966): Turbulent heat transfer in the separated reattached and redevelopment regions of a circular tube. AICHE J. 26, 303
Latornell, D. J., Pollard, A. (1986): Some observations on the evolution of shear layer instabilities in laminar flow through axisymmetric sudden expansions. Phys. Fluids 29/9, 2828
Laufer, J. (1950): J. Aeronaut. Sci. 17, 277 (cited by F. M. White 1974, Viscous Fluid Flow, McGraw-Hill Inc., USA)
Moon, L. F., Rudinger, G. (1977): Velocity distribution in an abruptly expanding circular duct. ASME J. Fluids Eng. p. 226
Runchal, A. K. (1971): Mass transfer investigation in turbulent flow downstream of sudden enlargement of a circular pipe for very high Schmidt numbers. Int. J. Heat Mass Transf. 14, 781
Tropea, C., Gackstatter, R. (1985): The flow over two-dimensional surface-mounted obstacles at low Reynolds numbers. ASME, J. Fluids Eng. 107, 489
White, F. M. (1974): “Viscous Fluid Flow,” (McGraw-Hill Inc., USA)
Yang, B. T., Yu, M. H. (1983): “The flow field in a suddenly enlarged combustion chamber. AIAA J. 21, 92
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1989 Springer-Verlag Berlin Heidelberg
About this paper
Cite this paper
Durst, F., Founti, M., Wang, A.B. (1989). Experimental Investigation of the Flow Through an Axisymmetric Constriction. In: André, JC., Cousteix, J., Durst, F., Launder, B.E., Schmidt, F.W., Whitelaw, J.H. (eds) Turbulent Shear Flows 6. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-73948-4_27
Download citation
DOI: https://doi.org/10.1007/978-3-642-73948-4_27
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-642-73950-7
Online ISBN: 978-3-642-73948-4
eBook Packages: Springer Book Archive