UNCONVENTIONAL METHODS FOR INFLUENCING FLUID FLOW. PART I. ACOUSTIC PUMPING.

摘要

The general system of equations describing the properties of an arbitrary fluid subjected to periodic disturbances are developed. A method of solution is proposed involving the Fourier expansion of the unknown functions to an arbitrary approximation. The problem of acoustic streaming between parallel plates is solved by the proposed method. Results of the streaming calculations are applied to a possible acoustic absorption pump. Significant pumping outputs are calculated but predicted efficiencies are shown to be very low. The relation between an acoustic pump and a jet pump is discussed and reason for the low calculated efficiencies stated. Another variant of acoustic pump,the resonant cavity pump,is discussed qualitatively and some experimental results presented. The pumping mechanism is shown to be the rectifying effect of a nozzle or orifice on the periodic flow between the resonant cavity and an infinite reservoir. The pump is shown to be of a reasonably high efficiency but limited to low outputs. (Author)