發(fā)布時(shí)間：2018-05-12 14:56

  本文選題：旋轉(zhuǎn)圓柱 + 轉(zhuǎn)速比��； 參考：《實(shí)驗(yàn)流體力學(xué)》2016年01期

【摘要】：投棄式海流剖面儀(Expendable Current Profiler,XCP)周圍流場是典型的旋轉(zhuǎn)圓柱繞流。探頭周圍流場對探頭的運(yùn)動(dòng)狀態(tài)起決定性作用,這直接關(guān)系到探頭的測量性能,因此有必要對旋轉(zhuǎn)圓柱周圍流場進(jìn)行實(shí)驗(yàn)研究。實(shí)驗(yàn)在循環(huán)水槽中進(jìn)行,通過PIV對雷諾數(shù)保持不變(Re=1000)、不同圓柱旋轉(zhuǎn)速度比(α=0、0.5、1.0、1.5、2.0、2.5、3.0、3.5、4.0、4.5和5.0)的圓柱下游尾流場進(jìn)行研究。通過選取不同旋轉(zhuǎn)速度比的任一時(shí)刻的瞬態(tài)流場,來分析旋轉(zhuǎn)對圓柱尾流結(jié)構(gòu)的影響。為了獲得流場的頻率信息,對所獲得流場信息進(jìn)行能譜分析來獲取渦旋的脫落頻率,并進(jìn)一步使用正交模態(tài)分解對流場進(jìn)行分析,給出了流場主要擬序結(jié)構(gòu)及其能量與轉(zhuǎn)速比的變化趨勢。發(fā)現(xiàn)圓柱旋轉(zhuǎn)改變圓柱尾流結(jié)構(gòu),使尾跡尺度變小。在旋轉(zhuǎn)速度比0≤α≤2.0時(shí),存在明顯的周期性渦旋脫落,并且渦旋脫落的頻率有逐漸升高的趨勢;而且當(dāng)轉(zhuǎn)速比2.0α≤5.0時(shí)尾跡流場的周期性減弱,渦旋脫落變得不明顯,流場表現(xiàn)出低頻、剪切層的區(qū)域特征。隨著轉(zhuǎn)速變大,渦旋尺度變小。在較高旋轉(zhuǎn)速度比時(shí),流場中能量被重新分布。
[Abstract]:The flow field around the cast current profiler Expendable Current Profiler XCP) is a typical flow around a rotating cylinder. The flow field around the probe plays a decisive role in the motion state of the probe, which is directly related to the measurement performance of the probe. Therefore, it is necessary to conduct an experimental study on the flow field around the rotating cylinder. The experiment was carried out in a circulating water tank. The wake flow field of the downstream cylinder was studied by means of PIV with the Reynolds number keeping constant and the rotation velocity ratio of different cylinders (偽 -0 / 0.51.0 / 1.51.51.5/ 2.5C / 2.0 ~ 3.54.0g / 4.5 and 5.0) respectively. The influence of rotation on the wake structure of a cylinder is analyzed by selecting the transient flow field at any time with different rotational velocity ratios. In order to obtain the frequency information of the flow field, the frequency of vortex shedding is obtained by energy spectrum analysis, and the flow field is analyzed by orthogonal mode decomposition. The main quasi-sequence structures of the flow field and the variation trend of the ratio of energy to rotational speed are given. It is found that the rotation of the cylinder changes the wake structure of the cylinder and makes the wake scale smaller. When the rotation velocity ratio is 0 鈮，

本文編號：1879049