A Stream Ribbon Seeding Strategy

Abstract

Streamline seeding algorithms have a long and rich history dating back over two decades. And in recent years algorithms for stream surface placement have been developed. However, stream ribbons have been generally overlooked. We present, to our knowledge, the first stream ribbon seeding strategy. Stream ribbons are a tool for visualizing vector fields and are a common extension of streamlines with the added benefit of conveying a fluid's twisting motion along the direction of flow. Presented in this short paper is a novel strategy for seeding stream ribbons in vector fields. The strategy exploits the flow's local helicity, an important property of flow identified over 40 years ago, to guide ribbon seeding. Seed points are prioritised based on a derived helicity field. A selection of user options including adjusting ribbon width, separating distance, and ribbon length filtering are applied to support visualization and cater to the users interests. A filtering method is also presented whereby the number of stream ribbons can be reduced in order to highlight the most helical flow features. We demonstrate the technique on various flow fields and report feedback from a domain expert in fluid mechanics.