| Abstract: | A series of experiments have been completed which use holographic interferometry to visualise a propane flame. The flame was produced by a 0·1 m diameter combustor, which swirled the flow to maximise its burning effeciency. The interferometric fringes obtained show the temperature profile across the flame and the turbulent burning cell structure within it. The holograms were made in close proximity to the flame using a high power ruby double pulse laser combined with sharp optical filters and a fast large aperture shutter.A semi-automatic system has been developed to digitise the complex interferometric fringe patterns generated. The system has been designed, using scanning optics held under computer control, to operate as an active microdensitometer. The microdensitometer has an optical resolution of 4000 × 4000 pixel points per picture and a potential resolution of 60 000 × 60 000 pixels. |
