Blade Vortex Interaction Studies. Department of Aerospace Engineering report 9803

This report contains a summary of the research conducted during the project entitled "Blade Vortex Interaction Studies", EPSRC grant number GR/K13547 in the Department of Aerospace Engineering, University of Glasgow. The original motivation for the study was to provide data to aid understanding of unsteady flows due to blade vortex interaction (BVI), which is a major source of acoustic and aerodynamic problems in helicopter rotor design. In particular knowledge of the effect of blade pitch upon a single vortex interacting with a blade was required. To reflect modern vane tip designs, the effect of a twin vortex system interacting with a blade was also to be studied. To perform the above investigations, a new BVI facility consisting of a rectangular blade instrumented with 72 surface mounted pressure transducers and a vortex generator were constructed which allowed tests at various fixed blade incidences. To provide a simulation of the vane tip vortex system a twin vortex generator was designed and constructed. The resulting data set is unique in its scope and quality, and provides a solid base for further research in this area. A preliminary analysis of the data was presented at an American Helicopter Society specialists' meeting (Masson et al. (1997)), and a journal paper is currently under review (Masson et al (1998)). The data are currently being subjected to a thorough analysis and a number of publications are in preparation.