本文選題：BLI進氣道 + 流動特性��； 參考：《南京航空航天大學》2016年碩士論文

【摘要】：BLI進氣道是一類不采用邊界層隔道、與機體結構融合的進氣道,特別適用于翼身融合體飛行器。本文設計了一種BLI進氣道,并對其展開了模擬外流條件下的仿真研究,獲得了其流動特性。在此基礎上,設計并搭建了BLI進氣道雙流路地面抽吸實驗臺,通過仿真驗證了實驗臺流動與待模擬流動的一致性。另外,本文還對BLI進氣道進行了初步的實驗研究,所獲結果和仿真結果基本一致。仿真和實驗研究表明,由于吸入了大量的來流邊界層,BLI進氣道內形成了不同于無邊界層吸入的常規(guī)S彎進氣道的特殊流動結構:BLI進氣道的進口段流場主要受鈍體繞流與邊界層相互干擾作用,流場中鞍點和分離線的數目、位置均隨出口馬赫數的變化而變化;在內通道中,吸入的邊界層在下壁面附近堆積,在第二彎段后半段,邊界層內的二次流逐漸發(fā)展成對渦,并將低能流卷向截面中間,最終在出口截面的中下半部形成了低總壓區(qū);并且,出口馬赫數越低、來流馬赫數越高、吸入的來流邊界層越厚,出口截面上的低能流堆積就越嚴重,對渦影響范圍越大,總壓恢復系數ζ也越低。在不同工況下,BLI進氣道的性能參數隨出口馬赫數的變化規(guī)律基本一致:隨著出口馬赫數的升高,BLI進氣道總壓恢復系數ζ先升高后降低,而常規(guī)S彎進氣道的ζ則隨之單調下降。另外,實驗臺的仿真校驗和初步實驗均表明,其可較為真實地模擬帶外流條件下BLI進氣道的流動特性,并可獲得不同的來流馬赫數、出口馬赫數、來流邊界層厚度等流動條件,因此該實驗臺的設計是成功的。
[Abstract]:The BLI inlet is a kind of inlet which does not use the boundary layer septum and is fused with the airframe structure. It is especially suitable for the wing body fusion vehicle. In this paper, a BLI inlet is designed, and its flow characteristics are obtained. On this basis, a two-way ground suction test bench for BLI inlet is designed and built, and the consistency between the experimental bed and the simulated flow is verified by simulation. In addition, a preliminary experimental study of the BLI inlet is carried out, and the results obtained are in good agreement with the simulation results. Simulation and experimental studies show that, The inlet flow field of the inlet is mainly affected by the interaction between the blunt body and the boundary layer due to the formation of a special flow structure in the inlet of the BLI inlet which is different from the conventional S-bend inlet without boundary layer inhalation. The flow field in the inlet section of the inlet is mainly affected by the interaction between the blunt body and the boundary layer. The number and position of saddle points and separation lines in the flow field vary with the Mach number at the exit. In the inner channel, the inhaled boundary layer accumulates near the lower wall, and in the second half of the second bend, the secondary flow in the boundary layer gradually develops into a pair of vortices. The lower the Mach number is, the higher the Mach number is, and the thicker the boundary layer of incoming flow is. The more serious the accumulation of low energy flow on the exit section is, the greater the range of influence on the vortex is, and the lower the recovery coefficient 味 of the total pressure is. Under different operating conditions, the performance parameters of the BLI inlet vary with the outlet Mach number. With the increase of the outlet Mach number, the total pressure recovery coefficient 味 of the BLI inlet increases first and then decreases, while that of the conventional S-curved inlet decreases monotonously. In addition, the simulation and preliminary experiments of the test bench show that the flow characteristics of the BLI inlet can be simulated more truthfully under the condition of the outflow, and the flow conditions such as the Mach number of the incoming flow, the Mach number of the outlet, the thickness of the boundary layer of the incoming flow can be obtained. Therefore, the design of the experimental platform is successful.
【學位授予單位】：南京航空航天大學
【學位級別】：碩士
【學位授予年份】：2016
【分類號】：V211.48

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1 寧樂;BLI進氣道流動特性的地面模擬方法和初步實驗研究[D];南京航空航天大學;2016年

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本文編號：1860236