Hydrodynamic performance of a fishlike undulating foil in the wake of a cylinder
Hydrodynamic performance of a fishlike undulating foil in the wake of a cylinder
复制标题
鱼状波状箔在圆柱体尾流中的水动力性能
DOI：
10.1063/1.3504651
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发表时间：
2010-11
影响因子：
4.6
通讯作者：
Shao, Xueming
中科院分区：
文献类型：
--
作者：
Pan, Dingyi;Deng, Jian;Yu, Zhaosheng;Shao, Xueming
采用改进的浸没边界方法，数值研究了鱼形波纹翼片在D形截面圆柱尾迹中的水动力性能。文中给出了各种控制参数对推力和输入功率的影响，包括翼片到D柱的距离、翼片波动的频率和相位角以及升沉运动的相位角。观察到在涡街上没有起伏的翼片可以获得推力，这是因为通过的涡会在翼面附近产生相对于主流的逆流。当波动翼片放置在D截面圆柱体后方不同距离处时，在圆柱体后方形成不同的尾迹结构。尾流区可分为三个区域：吸力区、推力增强区和弱影响区。与无箔或静止箔盒相比，箔片的起伏可以抑制剪切层的卷曲不稳定性和圆柱体上的涡脱落，从而显著扩大吸力区域。随着箔片与气缸之间距离的增加，箔片上的推力先增大后减小。当翼片位于气缸附近(主要是在吸力区)时，波动对翼片推进有不利影响，当翼片与气缸之间的距离超过某一临界值时，波动对翼片推进有积极作用。在不考虑垂荡运动且波动幅度较小的情况下，平均推力随起伏相角的变化不大，而受垂荡相角的影响较大。绕过漩涡的翼片承受最小推力和输入功率，而穿过漩涡的翼片承受更大的推力。垂荡和起伏之间的相角差是很重要的。
The hydrodynamic performances of a fishlike undulating foil in the wake of a D-section cylinder are numerically investigated by using a modified immersed boundary method. The results regarding the effects of various controlling parameters, including the distance between the foil and the D-cylinder, the frequency and the phase angle of foil’s undulation, and the phase angle of heaving motion on the thrust and the input power, are reported. It is observed that the foil without undulation in the vortex street can gain a thrust, as a result of the fact that the passing vortices produce reverse flows with respect to the mainstream in vicinity of the foil surface. When an undulating foil is placed at different distances behind the D-section cylinder, different wake structures form behind the cylinder. The wake area can be divided into three domains: suction domain, thrust enhancing domain, and weak influence domain. The undulation of the foil can inhibit the roll-up instability of the shear layers and vortex shedding from the cylinder and consequently significantly enlarge the suction domain, compared to the foil-free case or the stationary foil case. The thrust on the foil first increases and then decreases, as the distance between the foil and the cylinder increases. The undulation plays a negative role in the foil propulsion when the foil is located near the cylinder (largely in the suction domain) and a positive role when the distance between the foil and the cylinder is beyond a critical value. The mean thrusts do not vary significantly with the undulation phase angle when the heaving motion is not considered and the undulation amplitude studied is relatively small, instead, they are significantly affected by the phase angle of the heaving motion. The foil bypassing the vortices undergoes both minimum thrust and input power, whereas the one passing through vortices experiences a larger thrust. The phase angle difference between the heave and the undulation is important.
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影响因子：
4.1
作者：
GOLDSTEIN, D;HANDLER, R;SIROVICH, L
通讯作者：
SIROVICH, L
影响因子：
2.8
作者：
Liao, JC;Beal, DN;Triantafyllou, MS
通讯作者：
Triantafyllou, MS
影响因子：
64.8
作者：
D. Cushing;F. Jones
通讯作者：
D. Cushing;F. Jones
影响因子：
3.7
作者：
Beal, DN;Hover, FS;Lauder, GV
通讯作者：
Lauder, GV
影响因子：
3.7
作者：
Eldredge, Jeff D.;Pisani, David
通讯作者：
Pisani, David