2021 Volume 52 Issue 1 Pages 8-15
Poppet valves are often used as a pressure / flow rate control valve for a hydraulic system. Much research has been conducted on the characteristics of poppet valves. Hysteresis characteristics have emerged in pressure-flow characteristic experiments of poppet valves designed and prototyped by the author. In order to clarify the mechanism of this hysteresis characteristic, we firconfirmed the reproduction of hysteresis and confirmed the validity of the research policy. Specifically, we investigated the internal flow by CFD analysis and examined the reproduction of hysteresis characteristics by CFD. The CFD software used is Simerics MP +, which allows CFD analysis to be combined with the valve's equation of motion. First, the precision of CFD analysis was verified by confirming that the experimental values of in the reference and calculated values were in good agreement. Furthermore, CFD steady flow analysis of the internal flow was performed, and the validity of the calculation results such as the flow patterns, flow coefficient, and flow force was examined. As a result, it was clarified that there is a flow pattern that can be roughly divided into two types of internal flow with different flow rates. Then, by changing the flow rate in a time-dependent manner using CFD, we were able to reproduce the hysteresis characteristics that are in good agreement with the experimental results.
