Schlieren Imaging Of Banded Structures In Transitional Jets
Faculty of Computing, Health and Science
School of Engineering
Experiments have been conducted across the range of flows defining the laminar-to-turbulent transition of non-heated buoyant jets. Helium jets, of circular cross section, are ejected vertically upwards into a quiescent atmosphere and investigated using twin-mirror Schlieren imaging. An interesting transverse jet structure, similar to bands or stripes, is sometimes visualized in the laminar regime. These structures have a spatial scale greater than that of the nozzle exit diameter and span the entire width of the free jet. The paper provides an initial investigation into these structures.