Limited projections laser speckle tomography of complex flows

Different approaches are discussed applied to reconstruction of local flow parameters using line-of-sight laser probing. The first one is based on single projection measurement and detailed numerical simulation of flow pattern. The second one is based on multi-projectional line-of-sight measurement and reconstructing local flow parameters by solving inverse integral transforms. Holographic interferometry (HI) and speckle photography (SP) are used for laser probing of complex 3D media under study. Computer-assisted tomography (CAT) approach based on Radon integral transform is described and examples of reconstructed flowfields are given including compressible flows with shock waves. Statistical information about flow studied is extracted as well, and maps of local statistical turbulence parameters are quantitatively determined by using obtained SP-data and a new Erbeck–Merzkirch integral transform.