From ESPI to Digital Image Plane Holography (DIPH): Requirements, Possibilities and Limitations for Velocity Measurements in a 3-D Region

Abstract

The present work shows how the SPS-ESPI recordings can alternatively be analysed as Digital Image Plane Holographic (DIPH) recordings. When the SPS-ESPI recordings are analysed using a DIPH analysis, both the phase and intensity can be independently retrieved at each point of the fluid plane. The three velocity components in a fluid plane could be measured, since the phase maps detect an out-ofplane velocity component while the intensity data can be analysed with standard PIV methods to detect the two in-plane components. Finally, more than one fluid plane have been simultaneously recorded but independently reconstructed using DIPH. Some preliminary results from a convective flow with a He-Ne laser illustrate these features. A discussion of the requirements , possibilities and limitations of multiple plane DIPH is also presented.