OATAO - Open Archive Toulouse Archive Ouverte Open Access Week

LDV measurements in turbulent gaseous mixing induced by the Richtmyer-Meshkov instability: statistical convergence issues and turbulence quantification

Bouzgarrou, Ghazi and Bury, Yannick and Jamme, Stéphane and Joly, Laurent and Haas, Jean-François LDV measurements in turbulent gaseous mixing induced by the Richtmyer-Meshkov instability: statistical convergence issues and turbulence quantification. (2014) Journal of Fluids Engineering, 136 (9). ISSN 0098-2202

[img] (Document in English)

PDF (Author's version) - Depositor and staff only - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
2MB

Official URL: http://dx.doi.org/10.1115/1.4027311

Abstract

A statistical characterization of the turbulent flow produced in a vertical shock tube dedicated to the study of the Richtmyer-Meshkov instability (RMI) is carried out using Laser Doppler Velocimetry (LDV), time-resolved Schlieren images and pressure histories. The time evolution of the phase-averaged velocity field and the fluctuating velocity levels produced behind the shock wave are first investigated for different configurations of a pure air, homogeneous medium. This allows us to determine the background turbulence of the experimental apparatus. Second, the RMI-induced turbulent Air/SF6 mixing zone (TMZ) is studied both in its early stage of development and after its interaction with a reflected shock wave (reshock phenomenon). Here the gaseous interface is initially produced by a thin nitrocellulosic membrane trapped between two grids. One of the most consistent issue regarding such a process is the generation of a large number of fragments when the incident shock wave crosses the interface. These fragments are likely to corrupt the optical measurements and to interact with the flow. This work seeks to clarify the influence of these fragments on the statistical determination of the velocity field. In particular it is shown that statistical convergence cannot be achieved when the fragments are crossing the LDV measurement volume, even if a significant number of identical experiments are superimposed. Some specific locations for the LDV measurements are however identified to be more favourable than others in the Air/SF6 mixing configuration. This finally allows us to quantify the surplus of turbulence induced by the reshock phenomenon.

Item Type:Article
Audience (journal):International peer-reviewed journal
Uncontrolled Keywords:
Institution:French research institutions > Commissariat à l'Energie Atomique et aux énergies alternatives - CEA (FRANCE)
Université de Toulouse > Institut Supérieur de l'Aéronautique et de l'Espace - ISAE-SUPAERO (FRANCE)
Laboratory name:
Statistics:download
Deposited By: Yannick Bury
Deposited On:22 Jul 2014 16:08

Repository Staff Only: item control page