Structure of turbulence in an incipient-separating axisymmetric flow
- Univ. of Manitoba, Winnipeg, Manitoba (Canada). Dept. of Mechanical and Industrial Engineering
The relative intensity, skewness, and flatness of fluctuating streamwise velocity along the centerline of an 8 deg included angle conical diffuser show dramatic rapid growth in the final stages of the flow under the increasing influence of growing instantaneous reversals in the wall-layer. Pulsed-wire anemometry was effectively used for the measurement of quantitative instantaneous reversals and the turbulent flow field. In the severe adverse pressure gradient of the diffuser flow, the maxima of the streamwise and transverse fluctuating velocities, Reynolds shear stress, and turbulent energy production coincide and move away from their near-wall position in the pipe, also the velocity triple products show completely opposite nature as compared to the pipe flow. These measurements reveal the strong influence of instantaneous backflow on the structure of turbulence. The present results further corroborate the ability of the structural turbulence model of Nagano and Tagawa (1990) to predict velocity triple products in an axisymmetric diffuser flow.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 118725
- Journal Information:
- Journal of Fluids Engineering, Journal Name: Journal of Fluids Engineering Journal Issue: 3 Vol. 117; ISSN 0098-2202; ISSN JFEGA4
- Country of Publication:
- United States
- Language:
- English
Similar Records
EFFECTS OF A CHANGE IN WALL ROUGHNESS ON FULLY DEVELOPED FLOW IN A CIRCULAR PIPE
Granular flow in a wedge-shaped heap: Velocity field, kinematic scalings, and segregation