Dynamics and thermal behaviour of water sprays

Abstract A detailed study (dynamics, thermal and radiative transfer) concerning a single water spray is presented. It is based on comparisons between experimental and numerical results. The experimental part of this work uses both the Global Rainbow Thermometry (GRT) technique, providing informations about the size distribution and the mean temperature of a set of droplets, and a Fourier Transform InfraRed (FTIR) spectrometer yielding the radiative attenuation through the spray. Besides a numerical simulation of the spray is done using an Eulerian–Lagrangian approach. The radiative transfer problem is treated by a Monte Carlo Method using a Ck model and the Mie theory in order to define the spectral radiative properties of the medium. Evaluation of the numerical reliability of the code regarding temperature level predictions and attenuation ability of the spray is allowed by the experimental results. Furthermore, the numerical simulation can explain some experimental observations: the Sauter mean diameter evolution inside the spray is for example clearly related to the polydisperse feature of the spray.

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