Microscopic Clarification of a Non-Steady Non-Evaporating and Evaporating Spray and 3-D Numerical Simulation of a Burning Non-Steady Spray

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The fundamental data of droplet size in a non-steady spray was captured on a film with large size through a speckle killer and a telescopic lens system with super high spatial resolution. The main conclusions are 1) it is able to measure droplet size with the accuracy of 5 [μm] which is just the minimum in the world not only at the spray envelope but also at near the spray axis, 2) it is capable to visualize the vortex structure with large scale in a spray, 3) the large droplets exist at the vortex envelope and the small ones do inside the vortex and 4) it is possible to measure the velocity of droplets by photographing them with double exposure through the same system. The laser holography was applied to measure droplets size as 3D information. However, there is the problem of the selection of filter to obtain the reconstruction image. This is the next step of the selection of a suitable filter.The results of 3-D numerical calculation based on KIVA code where the technique of Large Eddy Simulation (LES) was built in with suitable model of the break-up and that of burning show that 1) it is possible to express the vortex structure with large scale appeared in a non-steady spray, 2) it is capable of presenting the time history of mixture fraction, temperature and rate of heat release, and 3) on the time history of rate of heat release it is able to representing the period of premixed burning, however,, it must be improve the prediction of the period of diffusion burning.