Affiliations: Department of Environmental & Ocean Engineering,
School of Engineering, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo
113-8656, Japan. | IBM Japan Ltd., 3-2-12, Roppongi, Minato-ku, Tokyo
106-8711, Japan.
Abstract: Particle tracking methods have been developed to visualize a
vector-field. The methods are efficient to show a large-scale and a small-scale
structure in the flow field clearly. However, initial positions of the
particles sometimes affect a visualized pattern. In addition, when a particle
lies on another one, it becomes difficult to display the particle and to
recognize the pattern. In this paper, we consider an enhancement of particle
tracking methods against those problems. First, we attempt to reduce the
dependence of pattern on the initial position and consider how to display a
particle occupies another particle position. Essence of our solution is
composed of homogenizing nascent-particles and a certain manipulation in a
pixel/voxel space. This solution is similar to that of line integral
convolution method (LIC). Secondly, accuracy of the visualization process is
discussed. Then, we make clear some pitfalls of LIC. Finally, a new technique
to overcome drawbacks of conventional particle tracking methods and LIC is
described. Several flow fields in two-dimensions and near surfaces are
visualized for demonstration of our proposed method.
Keywords: visualization error, vector field, particle tracking method, line integral convolution, homogeneous nascent position, flow visualization
