Experimental study on direct water hammer pressure characteristics in PMMA pipelines
To understand the water hammer pressure characteristics of viscoelastic pipelines,a series of shut-off valve water hammer tests were conducted by construction of a reservoir-pipeline-valve sys-tem model.The direct water hammer pressure change law generated by the shut-off valve for the Poly-methyl Methacrylate(PMMA)pipeline at the initial opening were 30％,100％of the end valves were studied.From the perspective of the constitutive relationship of viscoelastic materials,the influence mechanism of valve closing time on the direct water hammer of viscoelastic materials was analyzed.The 3D numerical simulations were conducted on the flow field at two different initial openings near the valve.The results show that the variation of direct water hammer pressure in viscoelastic pipelines is in-consistent with traditional water hammer theory.Direct water hammer pressure is related to the valve closing time and the valve initial opening time.The laws of"The faster the valve closes,the greater the direct water hammer pressure"and "The smaller the initial opening of the valve,the greater the direct water hammer pressure"are met.
viscoelastic pipelinedirect water hammervalve closing timevalve openingexperimental study
国家科技期刊平台
NSTL
万方数据
维普
