SOLID PARTICLE SEEDING USING CYCLONE GAS FLOW FOR OPTICAL FLOW VISUALIZATION DESIGN PARAMETERS TO BE CONSIDERED

摘要

Flow Visualization is an evolving field that has many advantages over intrusive testing methods. Commonly employed methods of Flow Visualization include Particle Image Velocimetry, Planar Laser-Induced Fluorescence, Laser Doppler Velocimetry and Schlieren Imaging. These not only vary in terms of the type of visualization equipment used, but also in terms of the way in which the Flow is finally visualized. Flow Visualization begins with flow "seeding" i.e. the introduction of discrete & definite alien particles into the flow. Seeding of Solid Particles in a compressible flow stream, using a Cyclone Jet is a much-favored and commonly employed method for Seeding, owing to its simplicity of design, construction and operation. Design Parameters that have to be considered for a cyclone-based seeding have been discussed in this paper, vis-a-vis the general properties of the seed particle and the nature of visualization techniques employed. An analytical view of Cyclone Seeding is also presented. Mei's particle tracking model is used as a base reference for the flow visualization. A simple design which was used for Particle Image Velocimetry testing, is also described.