CFD ANALYSIS AND IMPROVEMENT OF TORQUE DETECTED TYPE FLOW METER
Keywords:
flow meter, CFD analysis, laminar flow, pressure distribution, hydraulic lockAbstract
We propose a unique flow meter that uses a lateral flow force generated on a pressure sensing bar in a rectangular flow channel. The mathematical model, based on laminar viscous flow analysis, has been previously described and the design criterion was established from the fundamental characteristics. The test flow meter has also been investigated experimentally to clarify the torque versus flow characteristics. Although the meter performed well in terms of linearity and repeatability in the low flow rate region, the results deviated from the analytical results at high flow rates. This paper presents a theoretical analysis of the flow meter based on CFD (computational fluid dynamics). The aim is to examine the flow behavior and the pressure distribution inside the meter. CFD analysis is conducted over a range of dimensional configurations and boundary conditions. The flow versus torque characteristics are derived from pressure distribution results and compared with the analytical model. On the basis of CFD analysis, we propose a revised configuration of the flow meter, and verify its performance experimentally.
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