다양한 액유체 배관 시스템에서 수격 현상에 따른 유동특성연구

Abstract

In this paper, the characteristics of changes in pressure head and flow due to water hammer in various piping systems were studied using numerical analysis and experiments. This numerical study on the branch piping system can provide basic data for piping system design. Water hammer was simulated in single piping system and branch piping system using unsteady Reynolds--Averaged Navier-Stocks(URANS) model and user defined function(UDF) for compressible flow. The pressure change of the system was measured at 0.6 m on the upstream of the valve, and the flow rate change of each system was recorded at 30 m, 45 m, and 60 m on the upstream of the valve. As a result of the analysis, both the pressure waves patten of the single piping system and the branch piping system showed small errors compared to the experimental results, and the maximum was 9% in the branch piping system. In the form of the pressure wave, the instantaneous pressure drop was 76% compared to the peak in the branch piping system, unlike the single piping system. The flow rate change of the branch piping system showed a vibration that could not be seen in a single piping system, and the flow rate vibration was up to 28% when the pressure wave decreased.