简介:Wavediffractionoftwoconcentricporouscylinderswithvaryingporositywasstudiedbyusingananalyticalmethodbasedoneigenfunctionmatching.Thefluiddomainaroundthecylindersisdividedintothreesub-domainsandineachsub-domainaneigenfunctionexpansionofthevelocitypotentialisobtainedbysatisfyingtheLaplaceequation,theboundaryconditionsonthefreesurfaceandontheseabed.Theunknowncoefficientsofeigenfunctionexpansionsaredeterminedbyboundaryconditionsontheporoushulls.Inthepaper,theboundaryconditionsarebasedupontheassumptionthattheflowintheporousmediumisgovernedbyDarcy’slaw.Twoporous-effectparametersappliedontwoporouscylindersarefunctionsoftheverticalcoordinateinsteadoftheconstant.Waveloadingontheouterandinnercylinderispresentedinthenumericalresults.
简介:在比较几种常用的油气回收工艺的基础上,介绍了冷凝和吸附组合工艺油气回收装置适宜使用的环境,并以河北某油库冷凝和吸附油气回收装置的实际应用为例,从工程设计的角度,提出了几点关于该类油气回收装置需要注意的问题和改进建议。包括冷凝油油水分离器温度的控制和油气与冷凝油换热方法;油水分离器的设置和除水控制;制冷压缩机组的防爆措施和正压通风取风口的位置及取风质量;以及保冷节能措施等。