airfoil flutter 中文意思是什麼
airfoil flutter
解釋
機翼顫振-
This dissertation presents how to use the ultrasonic motor as an actuator to suppress the flutter of a two - dimensional airfoil section with a control surface. the ultrasonic motor, which features simple structure, high torque at low speed, small size, low weight and no electromagnetic contamination, is a promising actuator for the flutter suppression of small aircraft
超聲電機以其結構簡單緊湊、轉矩/質量比大、低速大扭矩、直接驅動，動態響應快、斷電自鎖和不產生磁場且不受外界磁場干擾等優點，有望成為一種非常有前途的作動器，用於小型飛機的機翼顫振主動抑制。 -
The flutter study of a two - dimensional airfoil with asymmetry freeplay
具有不對稱間隙的二元機翼顫振研究 -
Firstly, the airfoil ' s classic flutter ( at small attack angle ), stall flutter ( near the static stall angle ) and response ( at large attack angle ) are analyzed. it is found from the numerical results that " lock - in " will occur at certain freestream velocity range near the static stall angle, where the frequency of the vortex will be equal to the natural frequency and the flutter has the characteristic of self - induced oscillation. when the attack angle is far from the static stall angle, the vortex will have its own frequency, which differs from the natural frequency, and the flutter has the characteristic of forced oscillation
首先研究了二維翼型的古典顫振（小攻角） 、失速顫振（失速攻角）和動力響應問題（大攻角） ，得到以下結論：在靜態失速攻角附近的一定來流速度范圍內，分離渦會發生頻率鎖定現象，分離流的頻率與固有頻率趨于相同，這時的振動呈現自激振動的特點；遠離失速攻角時分離流頻率則擺脫固有頻率的影響，此時的振動具有強迫振動的特點。 -
Then the steady and unsteady subsonic, transonic and supersonic viscous flows around airfoil and some aircraft are numerically simulated. the 3 - dimensional unsteady navier - stokes equations are solved using the implicit lu - nnd algorithm, with baldwin - lomax turbulent model. on the basis of simulating unsteady viscous flow, coupling the structure dynamics equations, the problems of static aeroelasticity and flutter are investigated for wings and elevator
在模擬非定常粘性繞流的基礎上，與顫振運動方程相耦合，分別對機翼和全機流固耦合現象中顫振問題進行了研究，準確求解跨音速顫振臨界速度，分析機翼和全機的從亞音速到超音速范圍的顫振規律，並研究分析了機翼飛行迎角變化對顫振速度的影響。 -
In chapter 4, the aeroelastic model of the whole test rig is first established by using jones ’ s approximation of theodorsen ’ s unsteady aerodynamics load. then, the numerical simulations and wind tunnel experiments for the sub - optimal flutter suppression of the airfoil model are presented
數值模擬和風洞實驗研究表明，以超聲電機為控制面作動器可以有效地抑制翼段模型的顫振，顫振臨界速度提高了13 . 4 % ，數值模擬和風洞實驗結果基本吻合。 -
The dissertation presents the combined theoretical, numerical and experimental studies on the experimental modeling of the actuator, the design of test rig and control system, the modeling of two - dimensional airfoil aeroelastic system, the control design of active flutter suppression, and the effect of group delay in the digital filter on the stability of aeroelastic closed - loop system
本文通過理論分析、數值模擬與風洞實驗相結合的方法，研究了超聲電機作動器建模、翼段顫振實驗裝置和控制系統設計、二維翼段氣動彈性系統建模、顫振抑制控制律設計以及數字濾波器群時延對顫振抑制閉環系統穩定性影響等問題。 -
The numerical simulations agree well with the wind the tunnel experiments, and the critical speed is increased by 13. 4 %. chapter 5 presents the robust flutter suppression of the airfoil
數值模擬和風洞實驗表明，這兩種控制器是有效的，可將系統的顫振臨界速度提高23 . 4 % 。 -
Modal controller design of defective system and its application in flutter control of an airfoil
虧損系統模態控制設計及其在機翼顫振控制中的應用
分享友人