Product Overview - Racine Vortex - #2

Text version of the page

Tel: 262-639-6770 An everyday example of a vortex shedding phenomenon is a flag waving in the breeze: the flag waves due to the vortices shed by air moving across the flagpole. Within the flow meter, as flowing media moves across the strut or “bluff bar”, vortices are also shed but on a smaller scale. The meter transmits an ultrasonic beam through the vortex pattern downstream of the strut. As vortices are shed, the carrier wave of the ultrasonic signal is modified. This change in the carrier wave is measurable and moves in proportion to the number of vortices shed. Digital processing enables the vortices to be counted, and this value is converted into a velocity. Software converts velocity into a volumetric flow rate, in units of measure selected by the operator. Racine vortex flow meters utilize the smallest strut in the industry, allows for high sensitivity; superior performance at very low flow large turndown ratios; and low pressure drop. Through the use of an internal RTD and an external pressure sensor the flow meter software will compensate for changes in pressure temperature, to achieve an accurate mass flow measurement (gas Racine Vortex vs. Common Construction Flow Meter Selection Pipe head-on view Typical vortex shedding flow meters use a large bluff body, often in conjunction with a piezoelectric sensor or pressure transducer. These large bodies are needed in order to generate a pivot, torque or pressure differential of sufficient magnitude (see example below). Racine vortex flow meters utilize ultrasonic sensing technology, allowing the meters to perform with an extremely small bluff body. As a result, system pressure drop and meter turndown ratio are greatly improved. Typical 1.5" Gas Wafer Flow Meter. Bluff body blocks 43% of pipe cross-sectional area. Racine Vortex 1.5" Gas Wafer Flow Meter. Bluff body blocks 9% of pipe cross-sectional area. FLOW Transmitting Transducer Small Strut Shed Vortices Receiving Transducer ac T Racine vortex offers a sophisticated software program to aid in the flow meter selection process. The program accounts for system pressure and temperature, as well as density, viscosity and specific gravity. Select from a complete list of Metric and English engineering units, using default or customized reference standards for pressure and temperature. This program may be downloaded at no charge from www.racinevortex. 2 Vortex Flow Meters Operating Principle