FLOW VISUALISATION
This module consists of a specially-shaped duct which has a large working section with transparent window. The inlet of the duct is attached to the Air Flow Bench plenum chamber using quick-release clamps; the outlet is located into the bench exhaust. The duct has a rake of tubes from which fi laments of smoke emerge and flow around two-dimensional models held in the working section. The smoke fi laments can be made to visually show areas of steady and unsteady flow, thickening boundary layers, and separation. The rake is adjustable so that filaments can be made to contact the model surface at specific points of interest if desired.
The models are quickly and simply mounted, allowing the unit to be used for student project work.The unit produces considerable amounts of smoke which is safe and non-toxic but, to avoid the air in the laboratory becoming saturated, the unit includes a length of flexible tubing that connects the Air Flow Bench exhaust to either a suitable opening to atmosphere, or to an existing fan extraction system.
Note: The smoke generator uses compressed carbon dioxide. Due to transport regulations the unit is shipped with an empty gas bottle that requires filling before use.
Learning outcomes
- Demonstration of the flow patterns round a cylinder, flat plate, aerofoil and a sharp-edged orifice/slit.
