Affiliation:
1. Department of Mechanical Engineering, University of Delaware, Newark, DE 19716
Abstract
High-pass filtering of instantaneous two-dimensional PIV data is employed to educe vortices occurring in the axial plane of a self-similar turbulent axisymmetric jet. An automated method is used to identify the vortices and to measure circulation, tangential velocity, vorticity, and centrifugal force within their cores (defined here as the region within the largest closed streamline). Results include radial variation of these quantities within vortex cores, and the energy of vortices. We find that the vorticity is maximum at the vortex center and decreases monotonically with the radial coordinate. Results indicate that the center of a larger vortex spins faster than a smaller vortex (in an ensemble averaged sense); however, the trend reverses to give the expected result at the core edge. Vorticity results for different vortex radii collapse upon normalization. The average energy of vortices is seen to increase as the square of the vortex radius. In addition, three possible regimes of vortex number versus vortex size are suggested by our data.
Reference9 articles.
1. Adrian, R. J., Christensen, K. T., and Liu, Z.-C., 2000, “Analysis and Interpretation of Instantaneous Turbulent Velocity Fields,” Exp. Fluids, 29, pp. 275–290.
2. Agrawal, A., and Prasad, A. K., 2002, “Properties of Vortices in the Self-Similar Turbulent Jet,” Exp. Fluids, 33, pp. 565–577.
3. Agrawal, A., and Prasad, A. K., 2003, “Organizational Modes of Large-Scale Vortices in an Axisymmetric Turbulent Jet,” Flow, Turbul. Combust., 68, pp. 359–377.
4. Kundu, P., 1990, Fluid Mechanics, Academic Press, San Diego, CA.
5. Mayer, E. W., and Powell, K. G., 1992, “Similarity Solutions of Viscous Vortex Cores,” J. Fluid Mech., 238, pp. 487–507.
Cited by
19 articles.
订阅此论文施引文献
订阅此论文施引文献，注册后可以免费订阅5篇论文的施引文献，订阅后可以查看论文全部施引文献