No-moving-part valve for automatic flow switching

Flow control valve containing no moving components was developed for switching fluid flow passing through it into a parallel secondary path once the conditions in the main path reach a certain limit. No sensors or actuators are involved; the switching is caused by the inability of the Coanda effect to keep the flow attached to a wall that leads it into a particular outlet once a large resistance is met in this outlet. So far, there has been no method for designing such valves. To provide a guidance, this paper summarises experimental evidence about loading characteristics obtained with a considerable number of tested valve geometries.