Aerodynamic design of in-plane joined diamond-back wings for slender-body aerial vehicle across subsonic to Supersonic Mach Numbers

The study investigates the aerodynamic characteristics of novel in-plane joined diamond-back wing configurations designed for aerial vehicles across the subsonic-to-supersonic flight speeds (0.3 < M < 2.0). Unlike conventional joined-wing designs featuring out-of-plane designs, the two proposed in-plane variants, namely, IPX1 and IPX2 position the fore-wing and aft-wing within the same vertical plane ( h / b = 0.0), with both tandem wings connected with the fuselage, representing an innovative departure from traditional joined-wing architecture. The numerical results for joined-wing configurations are verified with the NASA Common Research Model, ONERA M6 wing, and Joined-Wing Research Aircraft experimental data. Numerical RANS-based CFD analysis, conducted using the CFD++ tool, evaluates performance across functions of Mach number ( M ), angles of attack ( α ), and sideslip angle ( β ) for both integrated aerial vehicles and isolated joined-wing configurations. The investigation reveals distinct Mach-dependent performance trends, where Body + IPX1 exhibits superior aerodynamic efficiency up to subsonic speeds ( M = 0.7), while Body + IPX2 dominates at transonic and supersonic regimes. Body-wing interference analysis demonstrates the robustness of joined-wing arrangements, with significant efficiency improvements. A particularly compelling advantage is the gradual stall progression of joined-wing variants, compared to the abrupt stall in conventional single-wing designs. The joined-wing design, namely IPX2, exhibits enhanced lateral acceleration characteristics, emphasizing superior maneuverability. The combined quantitative and qualitative aerodynamic analysis demonstrates in-plane joined-wing configurations as a transformative solution for next-generation high-performance, multi-regime aerial vehicles, offering enhanced aerodynamic efficiency, gradual stall characteristics, and enhanced maneuverability across flight regimes.