Experimental and Numerical Study of Confined Coaxial Turbulent Jets
نویسنده
چکیده
The turbulent mixing of a primary jet and its surrounding fluid in a pipe with inlet conditions that result in flow separation is studied. Detailed profiles of the axial mean and rms velocities have been measured with a laser Doppler anemometer. Measured spectra of axial velocity fluctuations show the presence of coherent structures. The performance of a two-equation turbulence model in conjunction with a finite-difference-based numerical prediction procedure was tested for selected previous experimental data. Computations using the presently measured inlet profiles were also performed, resulting in satisfactory agreement. It is concluded that numerical diffusion, streamline curvature, and the presence of coherent structures in the case of strong separation result in deteriorating agreement.
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