Measurements of Prandtl Number of an Elliptic Jet

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


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.


Minor Axis Turbulent Diffusivity Centrifugal Blower Passive Flow Control Turbulent Eddy Diffusivity 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

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

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