Flow velocity monitoring based on floating fibre ring vortex sensor

A novel and compact optical vortex flow meter is presented and experimentally demonstrated. The proposed structure can monitor the open area liquid flow velocity based on the von Karman vortex street and floating fibre ring vortex sensor. The optical fibre ring with floating foam sphere is attached behind a bluff body to measure the vortex shedding frequency in the liquid flow. This structure of flow meter occupies less area in the liquid channel, owing to very low consumption of the optical power loss of the sensor head, the flow meter is high power efficiency. Experimental results verify the new technique and demonstrate a vortex water flow meter at room temperature based on the fibre bending ring sensor is sensitive to liquid flow change.