- 學位論文
機翼釋放多個具鰭片彈體超音速流場參數探討
Parametric Investigation of Supersonic Flows over Multiple Stores with Fins Released from a Wing
摘要
在飛機與彈體進行分離時，將彈體順利地擊中目標物雖然重要，但如果所釋放之彈體撞擊到母體本身而導致損壞這並不是我們想要看到的，所以能將彈體順利分離也是值得關注的一環，因此本文使用商用軟體ESI CFD FASTRAN 研究超音速流通過機翼釋放多個具鰭片彈體之參數效應，在卡式座標下求解三維非穩態Euler方程式，採用多區塊Chimera網格系統，不同區塊網格系統重疊部分相互自動傳遞資訊，為驗證本文計算的正確性，單顆彈體重心瞬間軌跡與翻滾、俯仰、偏航角度、瞬間速度、角速度計算結果與實驗值比較後，趨勢分佈非常接近，進而增加彈體數量，並改變多彈體前施力倍增而後施力不變、前後施力倍增、超音速下攻角與馬赫數四個參數以探討分離多彈體之參數效應。
並列摘要
As for the release of stores from the aircraft, it is important that the target is hit and destroyed by the stores. However, it will not be allowed and expected if the mother aircraft is hit and damaged by the store it releases. Consequently, smooth separation of store and aircraft is also concerned. In this article, the commercial software ESI CFD FASTRAN is applied to study the parametric effects of supersonic flows around multiple stores with fins released from a wing. The three-dimensional, unsteady Euler is solved in the Cartesian coordinate. The Chimera multi-block grid system is utilized, and grid communication among multiple blocks is automatically implemented. To evaluate the accuracy of the present calculation, the calculated one-store instantaneous trajectory of center of gravity of store, angles of roll, pitch and yaw, velocity and angular rate are compared with those of experimental data. The satisfactory agreement is achieved. Then, the number of store is increased. As far as the multiple stores are concerned, four parameters are carried out to investigate the parametric effects of separated stores. The first is to increase the forward ejector force and keep rearward ejector force invariant, the second is to increase not only the forward ejector force but also the rearward ejector force, the third is to vary the angle of attack while the last is to change the Mach number.