本文選題：圓柱體 + 分離盤(pán)�。� 參考：《上海交通大學(xué)學(xué)報(bào)》2017年04期

【摘要】：使用大渦模擬方法,研究了高雷諾數(shù)時(shí)分離盤(pán)長(zhǎng)度對(duì)圓柱繞流特性的影響,對(duì)不同長(zhǎng)度分離盤(pán)下作用在圓柱體上的升力系數(shù)、拖曳力系數(shù)以及尾部流場(chǎng)的無(wú)量綱漩渦泄放頻率(strouhal數(shù))以及漩渦泄放形態(tài)進(jìn)行了對(duì)比分析.分析結(jié)果表明:依據(jù)升力系數(shù)以及拖曳力系數(shù)隨時(shí)間歷程的變化特性可以將分離盤(pán)長(zhǎng)度大致劃分為3個(gè)區(qū)間,分別為穩(wěn)定區(qū)間Ⅰ(分離盤(pán)長(zhǎng)度L=0D時(shí),D為圓柱直徑)、非穩(wěn)定區(qū)間Ⅱ(L=0.5D-1.0D)以及再穩(wěn)定區(qū)間Ⅲ(L=1.5 D-8.0D).當(dāng)分離盤(pán)長(zhǎng)度從區(qū)間I變化到區(qū)間Ⅱ時(shí),Strouhal(Sr)數(shù)出現(xiàn)突降;當(dāng)分離盤(pán)長(zhǎng)度從區(qū)間Ⅱ變化到區(qū)間Ⅲ時(shí),Sr出現(xiàn)突升.隨著分離盤(pán)長(zhǎng)度的增加,圓柱尾部流場(chǎng)的漩渦泄放形式從2S模式(即從圓柱兩側(cè)每次只泄放單個(gè)漩渦)逐漸轉(zhuǎn)化為2P模式(即從圓柱兩側(cè)每次同時(shí)泄放2個(gè)漩渦).
[Abstract]:In this paper, the influence of the separation disk length on the flow characteristics around a cylinder with high Reynolds number is studied by means of large eddy simulation, and the lift coefficient of the cylinder acting on the cylinder with different lengths is studied. The drag force coefficient and the dimensionless vortex release frequency (strouhal number) of the tail flow field are compared and analyzed. The results show that according to the variation characteristics of lift coefficient and drag force coefficient with time history, the length of separation disk can be roughly divided into three regions. They are stable interval 鈪，

本文編號(hào)：1934006