Garth, ChristophTricoche, XavierSalzbrunn, TobiasBobach, TomScheuermann, GerikOliver Deussen and Charles Hansen and Daniel Keim and Dietmar Saupe2014-01-302014-01-3020043-905673-07-X1727-5296http://dx.doi.org/10.2312/VisSym/VisSym04/155-164This paper presents powerful surface based techniques for the analysis of complex flow fields resulting from CFD simulations. Emphasis is put on the examination of vortical structures. An improved method for stream surface computation that delivers accurate results in regions of intricate flow is presented, along with a novel method to determine boundary surfaces of vortex cores. A number of surface techniques are presented that aid in understanding the flow behavior displayed by these surfaces. Furthermore, a scheme for phenomenological extraction of vortex core lines using stream surfaces is discussed and its accuracy is compared to one of the most established standard techniques.