Flow visualization study of grooved surface/surfactant/air sheet interactionThe effects of groove geometry, surfactants, and airflow rate have been ascertained by a flow-visualization study of grooved-surface models which addresses the possible conditions for skin friction-reduction in marine vehicles. It is found that the grooved surface geometry holds the injected bubble stream near the wall and, in some cases, results in a 'tube' of air which remains attached to the wall. It is noted that groove dimension and the use of surfactants can substantially affect the stability of this air tube; deeper grooves, surfactants with high contact angles, and angled air injection, are all found to increase the stability of the attached air tube, while convected disturbances and high shear increase interfacial instability.
Document ID
19890043107
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Reed, Jason C. (NASA Langley Research Center Hampton, VA, United States)
Weinstein, Leonard M. (NASA Langley Research Center Hampton, VA, United States)