Flexnozzle Steering of Analog Flow Diverters

摘要

The concept of using a sharp-edged nozzle whose two edges are not parallel (nor necessarily straight) is shown to be effective in changing the Flexistor valve behavior from digital to analog. In the Flexistor valve the flow diversion between two outlets is achieved by small movement of one side of a two dimensional sharp-edged nozzle. Test measurements of flow division between the two outlets as a function of rotation of one side of the nozzle are presented for several geometries. Useful geometries giving a good analog function are noted. A feedback model developed as an aid to understanding the device behavior and as a design tool is described. This simple and continuous flow division is applicable to flows of liquids, slurries, or gases. A particularly useful area of application is that of by-pass where a controlled proportion of a fluid stream is diverted around a device. The device may, for example, be a heat exchanger. Because of the simplicity of Flexnozzle actuation a simple downstream temperature sensor/actuator is all that is required to close the loop for temperature regulation. Many similar by-pass situtations exist in process engineering.