Experiments in Fluids

, Volume 37, Issue 4, pp 566–576 | Cite as

Mixing efficiency measurements using a modified cold chemistry technique

Original Paper

Abstract

The efficient mixing of fluids in compressible shear layers is still of fundamental importance to high-speed propulsion. To further understand the role of compressibility, measurements of mixing efficiency are performed in a convective Mach number=2.64 shear layer. The mean scalar field and estimated mixing efficiency are measured using a new “cold chemistry” technique utilizing the quenching of nitric oxide laser-induced fluorescence to mark regions of molecularly mixed fluid. Several different quenching partners are used to achieve statistically converged results using fewer images than previous techniques. The mixing efficiency (δm/δ) measured in this study at a Reynolds number of 1.9×106 is 0.64, following an increasing trend with both Reynolds number and compressibility when taken with previously measured cold chemistry results.

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Copyright information

© Springer-Verlag 2004

Authors and Affiliations

  1. 1.Mechanical Engineering DepartmentStanford UniversityUSA
  2. 2.Mechanical and Aerospace Engineering DepartmentRutgers UniversityPiscatawayUSA

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