Advertisement

Measurements of Prandtl Number of an Elliptic Jet

  • Z. K. Zhang
  • L. P. ChuaEmail author
Conference paper
  • 1.6k Downloads
Part of the Lecture Notes in Mechanical Engineering book series (LNME)

Abstract

The turbulent Prandtl number, Prt, distributions of a heated contoured contraction nozzle elliptic air jet with a 2:1 aspect ratio issuing into stagnant, unconfined surroundings were presented. The measurements were carried out with X-wire and three-wire (a cold wire in front of an X-wire) probes. The normalized RMS velocities in both lateral and span-wise directions were consistently smaller than those in the streamwise direction, indicating the anisotropy of the turbulence in the flow. The Prt evaluated based on the self-preserved data of Reynolds shear stress, \( \overline{\text{uv}} \), and heat flux, \( \overline{{{\text{v}}\uptheta}} \), at \( {\text{x}} = 30{\text{D}}_{\text{e}} \) decrease sharply from the center and only remained at a constant value of about 0.8 within the range of \( 0.4 \le {\text{y}}/{\text{L}}_{\text{y}} \le 1.8 \) along the major axis while a gradual increase is observed in the minor axis. A constant Prt in both axes should not be granted in the computational modeling and analysis of a heated elliptic jet.

Keywords

Minor Axis Turbulent Diffusivity Centrifugal Blower Passive Flow Control Turbulent Eddy Diffusivity 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

References

  1. Browne LWB, Antonia RA, Chambers AJ (1984) The interaction region of turbulent plane jet. Fluid Mech J 149:355–373CrossRefGoogle Scholar
  2. Chua LP, Antonia RA (1990) Turbulent Prandtl number in a circular jet. Int J Heat Mass Transf 33(2):331–339CrossRefGoogle Scholar
  3. Chua LP, Li YF, Zhou T (2004) Measurements of a heated square jet. AIAA J 42(3):578–588CrossRefGoogle Scholar
  4. Grinstein FF, DeVore CR (1996) Dynamics of coherent structures and transition to turbulence in free square jets. Phys Fluids 8(5):1237–1251MathSciNetCrossRefzbMATHGoogle Scholar
  5. Xu G, Antonia RA (2002) Effect of different initial conditions on a turbulent round free jet. Exp Fluids 33:677–683CrossRefGoogle Scholar
  6. Zhang ZK, Chua LP (2012) Mixing due to a heated elliptic air jet. Int J Heat Mass Transf 55(17–18):4566–4579CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  1. 1.Nanyang Technological University School of Mechanical and Aerospace EngineeringSingaporeSingapore

Personalised recommendations