Affiliation:
1. Department of Aerospace and Mechanical Engineering, The University of Arizona, Tucson, AZ 85721, www.ame.arizona.edu
Abstract
The mean and fluctuating characteristics of a plane, unsteady, laminar, wall jet were investigated experimentally for a constant wall-temperature boundary condition. Temperature and streamwise velocity profiles, including the downstream development of the thermal and hydrodynamic boundary layer thicknesses, were obtained through simultaneous hot and cold wire measurements in air. Even at relatively low temperature differences, heating or cooling of a floor surface sufficiently altered the mean velocity profile in the inner, near-wall region to produce significant effects on the jet stability. Selective forcing of the flow at the most amplified frequencies produced profound effects on the temperature and velocity fields and hence the time-averaged heat transfer and shear stress. Large amplitude excitation of the flow (up to 2 percent of the velocity measured at the jet exit plane) at a high frequency resulted in a reduction in the maximum skin friction by as much as 65 percent, with an increase in the maximum wall heat flux as high as 45 percent. The skin friction and wall heat flux were much less susceptible to low-frequency excitation.
Subject
Mechanical Engineering,Mechanics of Materials,Condensed Matter Physics,General Materials Science
Reference19 articles.
1. Amitay, M., 1994, “Theoretical and Experimental Investigations of a Laminar Two-Dimensional Wall Jet,” Ph. D. thesis, Faculty of Aerospace Engineering, Technion, Israel Institute of Technology, Haifa, Israel.
2. Amitay
M.
, and CohenJ., 1993, “The Mean Flow of a Laminar Wall Jet Subjected to Blowing or Suction,” Phys. Fluids, Vol. A5, pp. 2053–2057.
3. Amitay, M., and Cohen, J., 1997, “Instability of a Two-Dimensional Plane Wall Jet Subjected to Blowing or Suction,” J. Fluid Mech, in press.
4. Bajura
R. A.
, and CatalanoM. R., 1975, “Transition in a Two-Dimensional Plane Wall Jet,” J. Fluid Mech., Vol. 70, Part 4, pp. 773–799.
5. Bajura
R. A.
, and SzewezykA., 1970, “Experimental Investigation of a Laminar Two-Dimensional Plane Wall Jet,” Phys. Fluids, Vol. 13, pp. 1653–1664.
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