Use of PLIF and PIV Techniques to Analyze the Flow Mixing in Dilution Zone of an Aeronautic Combustor

摘要

This paper presents a study using PIV and PLIF techniques to investigate the mixing of eight jets flowing transversally into a pipe flow. These methods permit to identify the unsteady and steady features of the flow. The different vortical structures are revealed and quantitative information is obtained to characterize the mass transfer between the different flows. The analysis of the instantaneous velocity field indicates that the two counter rotative structures typical of this flow configuration, are stable close to the jet exit and become unsteady further downstream. The PLIF techniques applied on acetone permits to analyze the mixing of the different jet. Mean trajectories are determined with respect to the R ratio and the spreading of the jets is analyzed. Comparison between the velocity and the concentration results reveals the coupling between the aerodynamic and the mixture fields. Further treatments can be done in order to identify the influence of the Schmidt number on the mass and momentum diffusion. All these results were used to validate LES calculations (Priere, 2005).