民机的一种新型布局形式——翼身融合体飞机

 讨论了一种区别于机翼与圆柱机身的传统民机外形——翼身融合体（BWB）外形。从给定容积下减少浸润面积和摩擦阻力的考虑发展出了翼身融合体的概念。在满足系列设计约束条件下讨论了适于大型（800座）客机的翼身融合体的技术和商业上的可能性。概念设计研究表明，翼身融合体外形可获得比常规外形更好的性能。巡航升阻比可从传统外形的19提高至23。480座的BWB外形与同量级的传统外形（A380-700）相比，最大起飞重量可减少18%，每座位燃油消耗可减少32%，具有良好的环保性。通过气动载荷分布规律的反设计，翼型修型和三维优化设计等气动设计方法可以有效减阻和提高BWB的气动性能。由于BWB的高度融合性，讨论了多学科优化设计方法的重要性和有效性。BWB概念能够发展成BWB系列机，进一步提高巡航马赫数也是可能的。

A New Type of Transport-Blended Wing Body Aircraft

A new type of transport, which is different from the conventional cylinder fuselage plus wing but a blended wing body (BWB), is discussed. The concept of BWB is based on the consideration of reducing wetted area and friction drag for a given volume. The technical and commercial feasibilities of BWB concept, satisfying an unique set of design constraints for an 800-seat transport are discussed. The preliminary design study shows that the performance of BWB is better than that of the conventional configuration. Cruise L/D can reach 23 rather 19. For a class of 480-seat airplane, both maximum takeoff weight and fuel burn per seat of BWB may be reduced by 18% and 32% respectively, as compared to the conventional configuration (A380-700). Besides, BWB offers the potential of significant reductions in environment emissions and noise. The effective drag reduction and the performance improvement of BWB can be gained by using inverse design for a given spanwise aerodynamic load distribution, airfoil modification and 3-D optimization design. As BWB is a high integral configuration, the importance and effectiveness of multidisciplinary design optimization are discussed in the paper. BWB concept could be developed for a family of BWB airplanes with the potential for substantial commonality among its members. Increasing cruise Mach number for BWB is also possible.