The Channel Flow of a Density-Stratified Fluid About Immersed Bodies

Abstract

The flow of a density-stratified fluid about symmetric towed bodies was investigated both experimentally and theoretically. A cylinder and a slender body were towed through a linearly stratified fluid at various depths and the resulting lee waves were observed and recorded photographically in such a manner as to show the flow tracers as streamlines of the flow. A theoretical investigation was made using an inverse method of solution in which the bodies are generated by distributions of doublets of varying strength and location within the flow field. This theoretical solution predicts that the flow field will be symmetric about the model, only if the model is at the midplane of the flow channel and will be non-symmetric at any other location of the model. This prediction is qualitatively verified by the experimental observations. Theoretical solutions corresponding to the experimental observations were generated. It was found that good agreement was obtained between the theory and experiment as long as the model was towed at a symmetric plane of the channel. At other planes of towing the quantitative agreement between theory and experiment was not good.