Smoke and helium bubble visualization studies of incompressible flow past a jet-flap airfoil

Abstract

An exploratory study was performed on a jet-flapped airfoil in the Low Speed Flow Visualization Facility at the Naval Postgraduate School, Monterey, California. the purpose of this study was to evaluate the test facility for future work and to compare an old and a relatively new flow visualization technique. thee techniques are smoke flow and helium bubble flow. The study was conducted using various tunnel speeds and blowing rates of the jet flap. The varying of these parameters and the complexity of the jet flap flow allowed for an excellent evaluation of the best facility and the two flow techniques. As a result of the many photographs taken, a comparison was made between predicted jet stream deflection, using Spence's Theory, and those deflections measured on photographs.