Device for determining the flow rate of a fluid medium, following the differential pressure principle

摘要

A method often used for the inertia-free determination of the flow rate of fluid media is the method of forming the differential pressure across a throttle described exactly in terms of its construction within an effective pressure line in conjunction with the detection of the differential pressure. For a long time, the effective pressure in the throttle was produced by means of a reduced flow cross-section within a short path length. If the smallest flow rates are to be determined, very narrow cross-sections arise, which are associated with the risk of blockage of the effective pressure line. In the case of the device according to the invention, the effective pressure necessary for the measurement of the flow following the differential pressure method is produced by means of a sufficiently long throttle hose having a relatively large internal diameter. By this means, even the smallest flow rates can be measured without blockage of the effective pressure line.