中国电机工程学报
中國電機工程學報
중국전궤공정학보
ZHONGGUO DIANJI GONGCHENG XUEBAO
2012年
17期
76-81
,共6页
陈冬林%贠英%米建春%成珊%邓涛
陳鼕林%贠英%米建春%成珊%鄧濤
진동림%원영%미건춘%성산%산도
菱形射流%圆形射流%自由射流%湍流混合%粒子%图像测速测量%半值宽转换
蔆形射流%圓形射流%自由射流%湍流混閤%粒子%圖像測速測量%半值寬轉換
릉형사류%원형사류%자유사류%단류혼합%입자%도상측속측량%반치관전환
diamond jet%circular jet%free jet%turbulentmixing%particle image velocimetry (PIV) measurement%axis-switching
针对菱形和圆形2种不同出口形状的孔板自由射流,在出口雷诺数Re=72000(速度使用射流平均出口速度以,特征长度使用当量直径De)的情况下应用粒子图像测速(particle image velocimetry,PiV)技术对空气射流在初始段和过渡段的流场进行测量,并对2种不同形状出口的射流流动特性进行对比分析。结果表明:与圆形自由射流相比,菱形自由射流有更强的混合和卷吸周围流体的能力,具体表现在菱形自由射流的势流核更短,速度衰减和扩散更快以及湍流强度更大;另外,在菱形射流中还出现了长短轴半值宽变换的现象。
針對蔆形和圓形2種不同齣口形狀的孔闆自由射流,在齣口雷諾數Re=72000(速度使用射流平均齣口速度以,特徵長度使用噹量直徑De)的情況下應用粒子圖像測速(particle image velocimetry,PiV)技術對空氣射流在初始段和過渡段的流場進行測量,併對2種不同形狀齣口的射流流動特性進行對比分析。結果錶明:與圓形自由射流相比,蔆形自由射流有更彊的混閤和捲吸週圍流體的能力,具體錶現在蔆形自由射流的勢流覈更短,速度衰減和擴散更快以及湍流彊度更大;另外,在蔆形射流中還齣現瞭長短軸半值寬變換的現象。
침대릉형화원형2충불동출구형상적공판자유사류,재출구뢰낙수Re=72000(속도사용사류평균출구속도이,특정장도사용당량직경De)적정황하응용입자도상측속(particle image velocimetry,PiV)기술대공기사류재초시단화과도단적류장진행측량,병대2충불동형상출구적사류류동특성진행대비분석。결과표명:여원형자유사류상비,릉형자유사류유경강적혼합화권흡주위류체적능력,구체표현재릉형자유사류적세류핵경단,속도쇠감화확산경쾌이급단류강도경대;령외,재릉형사류중환출현료장단축반치관변환적현상。
Detailed mean flow and turbulence measurements were made in the near field and the transition field of two air/air turbulent jets issuing from a diamond orifice plate and a circular counterpart. Particle image velocimetry (PIV) was used for the measurements of the flow field with the exit Reynold number ( 72 000), based on the exit mean velocity Ue and the equivalent diameter De. Compared with the circular jet, the diamond jet is found to have a superior mixing capability. This is reflected by a shorter potential core, higher decay and spread rates of the jet and also the faster turbulence intensity growth. In addition, the phenomenon of axis switching is also found to occur in this jet.