Experiments in Fluids

, Volume 39, Issue 1, pp 48–55 | Cite as

Optical density and velocity measurements in cryogenic gas flows

  • O. S. JensenEmail author
  • J. P. Kunsch
  • T. Rösgen


This paper presents the application of optical measurement techniques in dense-gas flows in a heavy-gas channel to determine planar two-component (2C) velocity profiles and two-dimensional (2D) temperature profiles. The experimental approach is rather new in this area, and represents progress compared with the traditional techniques based on thermocouple measurements. The dense-gas flows are generated by the evaporation of liquid nitrogen. The optical measurement of both the velocity and density profiles is accomplished by the implementation of particle image velocimetry (PIV) and background-oriented schlieren (BOS) systems. Supplemental thermocouple measurements are used as independent calibrations to derive temperatures from the density data measured with the BOS system. The results obtained with both systems are used to quantify the dilution behavior of the propagating cloud through a global entrainment parameter β. Its value agrees well with the results obtained by earlier studies.


Particle Image Velocimetry Talcum Powder Release Chamber Phase Object Thermocouple Measurement 
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Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  1. 1.Institute of Fluid Dynamics (IFD)ETH ZurichZurichSwitzerland

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