简介:Inthepresentwork,computationalsimulationswasmadeusingANSYSCFXtopredicttheimprovementsinfilmcoolingperformancewithdualtrench.Dual-trenchconfigurationconsistsoftwotrenchestogether,onewidertrenchandtheotherisnarrowtrenchthatextrudedfromthewiderone.Severalblowingratiosintherange(0.5:5)wereinvestigated.Thepitch-to-diameterratioof2.775isused.Byusingthedualtrenchconfiguration,thecoolantjetimpactedthetrenchwalltwotimesallowingincreasingthespreadingofcoolantlaterallyinthetrench,reducingjetvelocityandjetcompletelycoveredonthesurface.Theresultsindicatethatthisconfigurationincreasedadiabaticeffectivenessasblowingratioincreased.Thespatiallyaveragedadiabaticeffectivenessreached57.6%foratM=2.Noobservedfilmblow-offatallblowingratios.Theadiabaticfilmeffectivenessofdualtrenchcaseoutperformedthenarrowtrenchcase,laidbackfan-shapedhole,fan-shapedholeandcylinderholeatdifferentblowingratios.
简介:摘要本文报道2例胰腺腺泡囊性转化。该病变非常罕见,是一种良性非肿瘤性病变。临床可有腹痛、消化不良、触及腹部肿块等非特异性表现,但大部分病例无临床症状。诊断需与较多见的胰腺囊性肿瘤性病变鉴别。治疗上可以随访或采取保守手术,避免误认为恶性肿瘤而过度手术治疗。