起始渦 的英文怎麼說
中文拼音 [qǐshǐguō]
起始渦
英文
starting vortex-
The story begins with a local eddy in the swirling gas and dust of the primordial galaxy.
話題要從原始星系的旋渦氣體和塵埃形成的一個局部渦流說起。The staring points of u exhibiting self - similarity and the symmetrical mode of the vortex street being destroyed almost overlap, both at x / h = 6. 0
U達到自相似狀態的起始點與渦街的對稱性被破壞的起始點是幾乎重合的，即在x h = 6 . 0處。In light of the limitation of fast fourier transform ( fft ) for the method of traditional spectrum analysis to analyze the unsteady signal, wavelet and wavelet analysis are made for the typical unsteady process signal of starting up and shut down with the good characteristic of simultaneous localization in both the time and the frequency domains based on the field test on the vibration of two - row placed units in lijiaxia hydropower station, in which the signal is decomposed into different frequency band, and then the weak signal is caught and the dominant frequency is picked up for the analysis of the vibration source
摘要基於李家峽水電站雙排機組振動的現場試驗研究，並且針對傳統頻譜分析方法傅立葉變換（ fft ）對于非平穩信號已力不從心這一缺陷，利用小波分析方法在時域和頻域上同時具有良好的局部化性質，通過對開停機這一典型非平穩過程信號進行小波及小波包分析，將其分解到不同頻帶內，獲取微弱信息和提取優勢頻率，並對其作振源分析，得出開停機初始時刻因水流不穩均出現強烈的振動現象，且低頻段信號能量最大，開停機過程水流脈動壓力和尾水渦帶擺動是引起定子基礎振動的主要原因。When the layers in the shear flow become wrinkled the motion grows complicated, especially when the wrinkles roll up into whirls.
當剪流中流體層開始起皺，尤其是皺褶捲曲成旋渦時，運動就復雜化了。On the base of the soft about the deformation of aerodynamic configuration of mav, the advanced controlling technique of the deformation o f aerodynamic configuration about the prototype mav will be explored. based on the characteristic of micro air vehicle, this paper abstracted the aerodynamic evaluation mathematics models, developed a aerodynamic engineering estimation program, all kinds of aerodynamic configuration was compared and analyzed, found the perfect configuration and got the prototype of mav. abstracted the model about the deformation of aerodynamic configuration on base of the method of vortex lattice, developed the program for researching the performance of the deformation of aerodynamic configuration
本文針對mav的具體特點，抽象出mav的氣動工程計算數學模型，建立起氣動工程估算環境，對各種氣動布局進行了氣動特性比較分析與綜合，尋求出理想的mav氣動布局方案並提出mav原型機，抽象出基於渦格法的氣動外形形變的數學模型，建立起氣動外形形變性能研究環境，探討新型的飛行控制方法和氣動力控制策略，在得出氣動外形形變模型的初始方案后，對其進行進一步的優化，最後得出理想的氣動外形形變執行機構組合陣列。分享友人