Lagrangian Visualization of Flow-Embedded Surface Structures

The powerful yet conceptually simple notions of Finite-Time Lyapunov Exponent (FTLE) and Lagrangian Coherent Structures provide a powerful framework for the analysis and visualization of complex technical flows. Their definition is simple and intuitive, and they are built on a deep theoretical foundation. We apply these concepts to enable the analysis of flows in the immediate vicinity of the boundaries of flow-embedded objects by limiting the Lagrangian analysis to surfaces closely neighboring these boundaries. To this purpose, we present an approach to approximate FTLE fields over such surfaces. Furthermore, we achieve an effective depiction of boundaryrelated flow structures such as separation and attachment over object boundaries and specific insight into the surrounding flow using several specifically chosen visualization techniques. We document the viability of our methods by presenting a number of application examples. Categories and Subject Descriptors (according to ACM CCS): ...

• Type: Journal
• Year: 2008
• Where: CGF
• Authors: Christoph Garth, Alexander Wiebel, Xavier Tricoche, Kenneth I. Joy, Gerik Scheuermann
• Keywords: CGF 2008, Complex Technical Flows, Finite-Time Lyapunov Exponent, Lagrangian Coherent Structures