振动与冲击
振動與遲擊
진동여충격
JOURNAL OF VIBRATION AND SHOCK
2015年
18期
118-122
,共5页
王玉川%高传昌%谭磊%曹树良
王玉川%高傳昌%譚磊%曹樹良
왕옥천%고전창%담뢰%조수량
淹没射流%轴对称腔体%空化%滞后效应%两相流动
淹沒射流%軸對稱腔體%空化%滯後效應%兩相流動
엄몰사류%축대칭강체%공화%체후효응%량상류동
submerged jet%axis-symmetrical cavity%cavitation%hysteresis property%two-phase flow
对轴对称腔体内淹没射流的空化流动特征进行了高速摄像观测和试验研究,得到了腔体内和下喷嘴出口管内流动的空化数与工作射流雷诺数(Re)的变化规律。试验研究发现,在一定的 Re 范围内,空化数随 Re 数发生跳跃变化,腔体内空化形态发生突变,空泡形态由突变前的小直径空泡剧变为突变后的大直径空泡。Re 减小变化过程发生空化数跳跃的 Rec 小于 Re 增大变化过程发生空化数跳跃的 Rec ,两者存在滞后效应。在试验的腔长范围(6≤Lc /d1≤13)内,Re 增大变化过程和 Re 减小变化过程的 Rec 均随腔长线性变化,但后者变化的斜率小于前者,滞后效应随着腔长的增长而扩大。
對軸對稱腔體內淹沒射流的空化流動特徵進行瞭高速攝像觀測和試驗研究,得到瞭腔體內和下噴嘴齣口管內流動的空化數與工作射流雷諾數(Re)的變化規律。試驗研究髮現,在一定的 Re 範圍內,空化數隨 Re 數髮生跳躍變化,腔體內空化形態髮生突變,空泡形態由突變前的小直徑空泡劇變為突變後的大直徑空泡。Re 減小變化過程髮生空化數跳躍的 Rec 小于 Re 增大變化過程髮生空化數跳躍的 Rec ,兩者存在滯後效應。在試驗的腔長範圍(6≤Lc /d1≤13)內,Re 增大變化過程和 Re 減小變化過程的 Rec 均隨腔長線性變化,但後者變化的斜率小于前者,滯後效應隨著腔長的增長而擴大。
대축대칭강체내엄몰사류적공화류동특정진행료고속섭상관측화시험연구,득도료강체내화하분취출구관내류동적공화수여공작사류뢰낙수(Re)적변화규률。시험연구발현,재일정적 Re 범위내,공화수수 Re 수발생도약변화,강체내공화형태발생돌변,공포형태유돌변전적소직경공포극변위돌변후적대직경공포。Re 감소변화과정발생공화수도약적 Rec 소우 Re 증대변화과정발생공화수도약적 Rec ,량자존재체후효응。재시험적강장범위(6≤Lc /d1≤13)내,Re 증대변화과정화 Re 감소변화과정적 Rec 균수강장선성변화,단후자변화적사솔소우전자,체후효응수착강장적증장이확대。
Experimental measurements and high speed video observations were carried out to study the cavitating flow properties of submerged jet in an axis-symmetrical cavity.The variations of cavitation number and Reynolds number (Re)of working jet in cavity chamber and outlet nozzle were obtained.From the experimental results,it is found that,in a certain range of Re,the jumping variation of cavitation number comes about,while the cavitating state in cavity chamber changes suddenly from small diameter bubbles to large diameter bubbles.The critical Reynolds number at the occurance of cavitation number jumping in the decreasing process of working jet Re is smaller than that in the increasing process of working jet Re,which shows a hysteresis effect between the two variation processes.Within the range of cavity chamber length in experiments,the critical Reynolds number is linearly related to the chamber length in both increasing and decreasing process of working jet Re variation,but the slope of cavitation number jumping in decreasing process is smaller than in increasing process.The hysteresis effect is enlarged as the chamber length increases.