ABSTRACT
Classical flow visualization techniques provide information about physical observables averaged along the pathlength of the probe radiation. Tomography extends the domain of flow visualization to new applications because it provides a framework for obtaining quantitative flow measurements from a set of line-of-sight images. From classical techniques such as shadowgraphy, interferometry, and absorption, three-dimensional distributions of physical observables can be reconstructed, provided a number of images of the flow are taken from different directions. Modeling of the tomographic process is useful for support of experiments. To carry out modeling studies, a priori information about the object is required. This knowledge may be available from numerical simulations of the flow field or other diagnostics. To simulate the actual experiment, projections are computed at various angles through the flow by carrying out line integration of the index of refraction or the absorption coefficient along each ray direction.
