简介:Anumericalsimulationisperformedtofindoutakeyvorticalstructureinthelaminar-turbulenttransition.Alow-speedstreakisgeneratedinsidealaminarboundarylayerusinganisolatedcuboidroughness,aimedatprovidinganenvironmentunstabletoouterdisturbances.Then,ashortdurationjetisissuedintotheboundarylayer.Whenthejetvelocityislow,somevorticesappearintheboundarylayer,butthetransitionoftheboundarylayerdoesnottakeplace.However,whenthejetvelocityexceedsacertainthreshold,twovorticesnewlyappearabovetheelongatedlegsofaV-shapedvortexandonlyoneofthemisstretchedandsurvives.Afterthat,vorticesaregeneratedoneafteranotheraroundthesurvivedone.Bycomparingthedecayedandthesurvivedvortices,itisfoundthatthedifferenceintheirheightsisthekeycharacteristicwhichleadstothetransition.
简介:摘要当前我国建筑行业的发展,对于城市的现代化建设起到重要的影响作用,而房屋建筑由于人们的生活息息相关,因此房屋建筑的质量受到社会与人们的广泛关注。针对于现代房屋建筑工程中存在的质量通病需要进行针对性的研究,从而减少工程经济效益的发挥,减少建筑的使用寿命。本文主要针对的是房屋建筑工程的特点与质量通病分析,结合具体的情况采取对应的防止措施,确保房屋建筑工程的质量与使用功能安全性。