發(fā)布時間：2018-01-28 00:10

  本文關(guān)鍵詞： 水翼 邊界層轉(zhuǎn)捩 γ-Reθt轉(zhuǎn)捩模型 尾渦脫落　出處：《水利學(xué)報》2017年08期 　論文類型：期刊論文

【摘要】：邊界層轉(zhuǎn)捩是影響水翼繞流水動力學(xué)特性的關(guān)鍵因素之一。為了探究γ-Reθt轉(zhuǎn)捩模型在低湍流度來流下水翼邊界層轉(zhuǎn)捩及尾渦脫落預(yù)測中的適用性,本文基于耦合γ-Reθt轉(zhuǎn)捩模型和SST k-ω模型的轉(zhuǎn)換SST模型,對0°攻角的NACA0009鈍尾緣水翼繞流進(jìn)行了數(shù)值計算。分析了轉(zhuǎn)捩SST模型對網(wǎng)格尺度的敏感性,預(yù)測了邊界層和尾跡區(qū)流場及不同雷諾數(shù)下水翼尾渦脫落特征,并與實驗數(shù)據(jù)和SST k-ω模型計算結(jié)果進(jìn)行了對比。結(jié)果表明:隨近壁面第一層網(wǎng)格尺度y+的增大,水翼邊界層轉(zhuǎn)捩位置沿流向后移,最大y+值小于1時,預(yù)測的轉(zhuǎn)捩位置趨于一致;與SST k-ω模型相比,轉(zhuǎn)捩SST模型可以求解層流邊界層,避免了在邊界層和尾跡區(qū)對渦黏系數(shù)的過高預(yù)測,得到的邊界層厚度和水翼尾跡區(qū)流動參數(shù)與實驗結(jié)果更為接近;轉(zhuǎn)捩SST模型可以較準(zhǔn)確預(yù)測水翼尾渦脫落頻率隨雷諾數(shù)增大而增加的變化趨勢,水翼尾渦脫落頻率預(yù)測值與實驗結(jié)果的最大相對誤差為6.2%。
[Abstract]:Boundary layer transition is one of the key factors affecting the dynamic characteristics of hydrofoil around income. In order to explore the applicability of 緯 -Re 胃 t transition model in prediction of hydrofoil boundary layer transition and wake shedding under low turbulence. Based on the coupled 緯 -Re 胃 t transition model and the SST k- 蠅 model, the transformed SST model is presented in this paper. The flow around the flank of NACA0009 with 0 擄angle of attack is numerically calculated, and the sensitivity of transition SST model to grid scale is analyzed. The flow field in the boundary layer and wake region and the wake shedding characteristics of hydrofoil under different Reynolds numbers are predicted. The results are compared with the experimental data and the SST k- 蠅 model. The results show that with the increase of the scale y of the first layer near the wall, the transition position of the hydrofoil boundary layer moves backward along the flow direction. When the maximum y value is less than 1:00, the predicted transition position tends to be consistent. Compared with the SST k- 蠅 model, the transition SST model can solve laminar boundary layer and avoid the excessive prediction of vortex viscosity coefficient in the boundary layer and wake region. The thickness of the boundary layer and the flow parameters of the hydrofoil wake are closer to the experimental results. The transition SST model can accurately predict the variation trend of wake shedding frequency with the increase of Reynolds number. The maximum relative error between the predicted value and the experimental results is 6.2.
【作者單位】： 中國農(nóng)業(yè)大學(xué)水利土木工程學(xué)院;北京市供水管網(wǎng)系統(tǒng)安全與節(jié)能工程技術(shù)研究中心;
【基金】：國家自然科學(xué)基金項目(51409147) 中央高�；究蒲袠I(yè)務(wù)費專項資金項目(2015SYL001)
【分類號】：TV136
【正文快照】： 2.北京市供水管網(wǎng)系統(tǒng)安全與節(jié)能工程技術(shù)研究中心,北京100083)1研究背景水力機械葉片表面的流動轉(zhuǎn)捩,直接影響葉片升阻力、尾渦脫落頻率等宏觀流動特征及機組的水力性能。水翼是水力機械葉片的簡化模型,在低湍流度自由來流條件下,光滑水翼壁面邊界層存在從層流到湍流的自然轉(zhuǎn)，

本文編號：1469209