Flow study over bluff bodies based on visualization technique

Abstract

Flow visualization is a very important part of the study of fluid dynamics processes analyzed in many fields of physics and engineering. The present study explores flow visualization experiment technique applied to blunt shaped bluff bodies placed inside towing tank. Vortex shedding in circular cylinders has been studied in depth, being able to visualize the classical von Kármán vortex street. Moreover, the vortex shedding in cylinders of square section has been studied so that the differences between bodies with different section can be compared. A comparison between theoretical and experimental values of vortex shedding frequencies has been obtained; a high correlation with them shows the appropriate experimental procedure. Finally, this paper tries to advocate the use of the towing tank technique as a method to support the theoretical lectures related with some fluid mechanics concepts quite difficult to understand.