CHARACTERISTIC SCALES IN A SPRAY FROM A DIESEL INJECTOR STUDIED WITH WAVELET MULTIRESOLUTION ANALYSIS

摘要

Wavelet multiresolution analysis has been applied to digital images of ethanol sprays injected into air at atmospheric pressure and at room temperature. The imaging was performed with laser-sheet imaging using the 308 nm light from a XeCl excimer laser, Image capturing was performed with a CCD camera. The importance of different scales in the turbulent structure of the sprays was easily recognized using wavelet multiresolution analysis. It was observed that the intermediate and small scale levels contained information of such important phenomena as the spray break-up. This was not easily recognized in the original images, due to averaging over all scales.