船舶力学
船舶力學
선박역학
Journal of Ship Mechanics
2015年
11期
1295-1303
,共9页
董洪辉%王宝寿%陈玮琪%张珂
董洪輝%王寶壽%陳瑋琪%張珂
동홍휘%왕보수%진위기%장가
泡状流%激波%空化
泡狀流%激波%空化
포상류%격파%공화
bubbly flow%shock wave%cavitation
文章针对定常可压缩泡状流中回转体的空化绕流进行了数值模拟,在给定来流速度和环境压力的条件下,对不同含气率下的空化与激波的相互作用进行了研究。首先,对含气率为0的情形进行计算并同试验数据进行对比,证明所采用的计算模型是可信的。其次,改变流场含气率从0至0.5进行计算,结果表明,随着含气率的增大,流场的可压缩性随之增强,体现为数值模拟得到了回转体绕流流场的3种波系,包括回转体头部处的脱体激波、分离面处的膨胀波和空泡尾端的斜激波。而空化与激波的相互作用则体现为:头激波削弱了空化效应,使得空化区域减小;由于空泡外形的影响,使得空泡尾端出现了斜激波;含气率超过一定值,空泡已经无法闭合在物面上,而是闭合在空泡尾端的激波面上,体现为空泡尾端壁面逆压梯度趋于平缓。计算结果揭示了泡状流中空化与激波相互作用的新的物理现象。
文章針對定常可壓縮泡狀流中迴轉體的空化繞流進行瞭數值模擬,在給定來流速度和環境壓力的條件下,對不同含氣率下的空化與激波的相互作用進行瞭研究。首先,對含氣率為0的情形進行計算併同試驗數據進行對比,證明所採用的計算模型是可信的。其次,改變流場含氣率從0至0.5進行計算,結果錶明,隨著含氣率的增大,流場的可壓縮性隨之增彊,體現為數值模擬得到瞭迴轉體繞流流場的3種波繫,包括迴轉體頭部處的脫體激波、分離麵處的膨脹波和空泡尾耑的斜激波。而空化與激波的相互作用則體現為:頭激波削弱瞭空化效應,使得空化區域減小;由于空泡外形的影響,使得空泡尾耑齣現瞭斜激波;含氣率超過一定值,空泡已經無法閉閤在物麵上,而是閉閤在空泡尾耑的激波麵上,體現為空泡尾耑壁麵逆壓梯度趨于平緩。計算結果揭示瞭泡狀流中空化與激波相互作用的新的物理現象。
문장침대정상가압축포상류중회전체적공화요류진행료수치모의,재급정래류속도화배경압력적조건하,대불동함기솔하적공화여격파적상호작용진행료연구。수선,대함기솔위0적정형진행계산병동시험수거진행대비,증명소채용적계산모형시가신적。기차,개변류장함기솔종0지0.5진행계산,결과표명,수착함기솔적증대,류장적가압축성수지증강,체현위수치모의득도료회전체요류류장적3충파계,포괄회전체두부처적탈체격파、분리면처적팽창파화공포미단적사격파。이공화여격파적상호작용칙체현위:두격파삭약료공화효응,사득공화구역감소;유우공포외형적영향,사득공포미단출현료사격파;함기솔초과일정치,공포이경무법폐합재물면상,이시폐합재공포미단적격파면상,체현위공포미단벽면역압제도추우평완。계산결과게시료포상류중공화여격파상호작용적신적물리현상。
The numerical simulation on the cavitating flow around an axis-symmetrical body in the steady compressible bubbly flow was simulated, and the interaction between cavitation and shock wave under dif-ferent air volume fractions with the constant flow velocity and operating pressure was investigated. Firstly, to verify the used calculation model, the case which air volume fraction takes 0 in the incoming flow was cal-culated and shows a good agreement with the experimental result. Secondly, more cases with air volume frac-tions varying from 0 to 0.5 were calculated. The results show that with the increase of air volume fractions, flow field becomes more compressible. This result was confirmed by the appearance of three kinds of wave systems, including detached shock wave before the head, expansion wave at separation surface and oblique shock wave after cavity tail. The interaction between cavitation and shock wave is reflected as follows: bow shock before caviting region weakens cavitation effects, making caviting region decrease; cavity generated by cavitation results in occurrence of oblique shock;cavity closure point cannot locate on the body surface but on the shock surface, which can be confirmed by the adverse pressure gradient at the end of cavity. These results revealed a new physical phenomenon which existed in the interaction process between the cavity and the shock wave in compressible bubbly flows.