How Vortex Shedding Flow Meters Work
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How Vortex Shedding Flow Meters Work When a fluid passes by an object or obstruction, oscillations can occur. Examples of these oscillations in nature include the whistling caused by wind blowing by the branches of trees, the swirls produced downstream of a rock in a rapidly flowing river, and the waving of a flag in the wind. Note that in all of these examples, when the flow is slowed, the oscillations stop. That is, the whistling stops when the wind dies down, the water flows calmly around the rock when the river is not flowing rapidly, and the flag does not wave in a mild breeze. Vortex shedding flow meters use a bluff body obstruction. Increasing flow increases the frequency of oscillation. A sensor detects the oscillations and an electronic transmitter generates a flow measurement signal. |