Experimental study of the switching characteristics of bistable amplifiers in the turbulent flow regime

A parametric investigation was conducted on a large scale model of a wall attachment bistable amplifier, with the object of measuring the switching times, as well as the steady state pressure distributions on the bistable walls and at the bistable output. As a first approach bistable configurations having no vents or splitter but only two straight attachment walls of variable length, set-back and angle, have been studied. Experimental data was obtained from oscilloscope recordings of velocities and pressure measured in the control and output channels of the bistable, following the application of a step signal in the control port. Tests were conducted for two different aspect ratios of the amplifier, and for control ports open and closed. The results are expected to prove useful for future comparisons with available theories of bistable switching, and for an experimental optimization of the bistable amplifier, made by taking into account not only its steady state but also its dynamic behaviour.