Droplet-Local Line Integration for Multiphase Flow

TL;DR

This paper introduces a novel droplet-local line integration method for multiphase flow visualization, which isolates droplet-specific velocities to improve the clarity of flow structures and aid in analyzing droplet dynamics.

Contribution

The paper presents a new technique for deriving droplet-local velocity fields by decomposing the original flow, enabling clearer visualization of droplet behavior in multiphase flow data.

Findings

Shorter and less tangled integral lines improve analysis.

Visualization of removed velocity components provides contextual understanding.

Method effectively reveals droplet dynamics in two-phase flow.

Abstract

Line integration of stream-, streak-, and pathlines is widely used and popular for visualizing single-phase flow. In multiphase flow, i.e., where the fluid consists, e.g., of a liquid and a gaseous phase, these techniques could also provide valuable insights into the internal flow of droplets and ligaments and thus into their dynamics. However, since such structures tend to act as entities, high translational and rotational velocities often obfuscate their detail. As a remedy, we present a method for deriving a droplet-local velocity field, using a decomposition of the original velocity field removing translational and rotational velocity parts, and adapt path- and streaklines. Generally, the resulting integral lines are thus shorter and less tangled, which simplifies their analysis. We demonstrate and discuss the utility of our approach on droplets in two-phase flow data and visualize the removed velocity parts employing glyphs for context.