NUMERICAL INVESTIGATION OF X-45A TYPE UNMANNED COMBAT AIR VEHICLE

Abstract

In this paper, the low-speed aerodynamic performance of unmanned combat air vehicle (UCAV) X-45 delta wing was investigated by a numerical method using computational fluid dynamic approaches (CFD). The investigation was conducted with X-45 and the formation of leading-edge vortices (LEV) and vortex breakdown was studied by a varying angle of attack with the range of 5° to 30° at the Reynolds number of 10,000 using the SST turbulence model and are compared with experimental data to validate simulation accuracy of CFD. Stall conditions happened at around 30°, averaged vorticity layer demonstrates a prolonged form that goes along by narrow recirculation zones neighboring to the wing surface. Detail about flow field, including LEV formation, vortex breakdown, interaction, and nonlinear aerodynamic characteristics of X-45 was presented and discussed.

Keywords

• LEV
• CFD
• delta wing
• X-45

X-45A Tipi İnsansız Muharebe Hava Aracının Nümerik Olarak İncelenmesi

Abstract

Bu çalışmada, insansız savaş hava aracı (SİHA) X-45 delta kanadının düşük hızlı aerodinamik performansı hesaplamalı akışkanlar dinamiği yaklaşımları (HAD) kullanılarak sayısal bir yöntemle incelenmiştir. İnceleme X-45 ile yürütülmüş ve öncü girdapların (LEV) oluşumu ve girdap kırılması, SST türbülans modeli kullanılarak Reynolds sayısı 10.000'de 5° ila 30° aralığında değişen bir hücum açısı ile incelenmiştir. CFD'nin simülasyon etkinliğini doğrulamak için daha önceden yapılan deneysel verilerle karşılaştırılmıştır. Stol koşulları yaklaşık 30°'de meydana gelmiş, ortalama girdap katmanı, kanat yüzeyine komşu dar döngüsel bölgeleri boyunca uzanan uzun bir form göstermektedir. LEV oluşumu, girdap bozulması ve etkileşimi ve X-45'in doğrusal olmayan aerodinamik özellikleri dahil olmak üzere akış alanı hakkında ayrıntılar sunulmuş ve tartışılmıştır. 

Keywords

• LEV
• CFD
• delta kanat
• X-45

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