Multidisciplinary Design Optimization of a Transonic Commercial Transport with Strut-Braced Wing

Abstract

The multidisciplinary design optimization of a strut-braced wing (SBW) aircraft and its bene ts relative to a conventional cantilever wing con guration are presented. The multidisciplinary design team is divided into aerodynamics, structures, aeroelasticity, and the synthesis of the various disciplines. The aerodynamic analysis uses simple models for induced drag, wave drag, parasite drag, and interference drag. The interference drag model is based on detailed computational uid dynamics analyses of various wing-strut intersections. The wing structural weight is calculated using a newly developed wing bending material weight routine that accounts for the special nature of SBWs. The other components of the aircraft weight are calculated using a combination of NASA's ight optimization system and Lockheed Martin aeronautical systems formulas. The SBW and cantilever wing con gurations are optimized using design optimization tools (DOT) software. Of ine NASTRAN aeroelastic analysis results indicate that the utter speed is higher than the design requirement. The minimum take-off gross weight SBW aircraft showed a 9.3% advantage over the corresponding cantilever aircraft design. The minimum fuel weight SBW aircraft showed a 12.2% fuel weight advantage over a similar cantilever aircraft design.

Numerical prediction of the interference drag of a streamlined strut intersecting a surface in transonic flow

“…In hope that his family and grandchildren will live in great happiness lift coefficient of the strut-wall configuration C n normal force coefficient [1,2,3]. Within the MDO framework, the structural and aerodynamic analysis modules are linked together with an optimizer in order to minimize the aircraft take-off gross weight or any other suitable objective function subject to some constraints.…”

“…Grasmeyer [1], Gern et al [2], and Gundlach et al [3] presented the approach employed to study the benefits of the strut-braced wing concept within an MDO framework. The strutbraced wing was designed to carry 325 passengers at a cruise Mach number of 0.85 and to have a range of 7,500 nautical miles.…”

Multidisciplinary design optimization of blended-wing-body transport aircraft with distributed propulsion

“…The wing bending material weight is calculated using a double plate model [26]. The remaining components of the wing weight are estimated using NASA Langley's Flight…”

Multidisciplinary Design Optimization of Low-Airframe-Noise Transport Aircraft

“…30 Wing weight is calculated using a combination of NASA Langley's Flight Optimization Software (FLOPS) 31 and a piecewise-linear beam model, representing the wing structure as an idealized double-plate model, and in the case of SBW taking into account the influence of the strut on the structural wing design. 32 Weights of the remaining components of the wing are calculated with FLOPS. A detailed description of the wing structures model can be found in.…”

“…Full details of the code are given in. 32,34,35 The objective function selected is to minimize Take-Off Gross Weight (T OGW ). A total of 17 design variables are used for cantilever wing aircraft (Table 1) and they include aircraft geometric properties (main wing, vertical tail, engine location, and high lift system) and operating parameters such as average cruise altitude, maximum sea level static thrust and fuel weight.…”