CFD 해석을 이용한 배관지지용 유압식 완충기의 밸브 스프링 설계 및 지지하중 평가

Abstract

Hydraulic snubbers used for supporting the pipes in plant structures can absorb shocks applied to the pipes under normal loading conditions and in turn do not transmit any load to the structures. In contrast, under extreme dynamic loading conditions, such as an earthquake-induced force, these snubbers secure the pipes and carry the load to the structures to reduce pipe vibration. Because the operating behavior of these snubbers is governed by complex interactions of their various internal components, a high technical skill is required for the sophisticated design of these snubbers. In this study, we first obtained a full understanding of the overall structure of a hydraulic snubber and the operating principles of its control valves. We then conducted computational fluid dynamics (CFD) simulations of hydraulic oil flow through the control valves by considering the internal positions of the valve components under tension and compression of the snubber. Furthermore, based on the CFD results, the valve spring stiffness was designed to achieve the target performance, and the load-carrying capacity of the snubber was evaluated under tensile and compressive conditions. We also discussed the effect of temperature-dependent viscosity of hydraulic oil on the load-carrying capacity of the snubber. This study provides a basis for the structural design of a hydraulic snubber and the selection of hydraulic oil.