Supersonic low-boom and low-drag coupled area rules for transport efficient design

Environmentally sustainable supersonic transport (SST) has become one trend of future civil aviation. Next-generation SST attaches great importance to sonic boom mitigation and drag reduction. It also puts forward demands to efficient and significant approaches to supersonic aircraft design. The paper innovatively couples Whitham sonic boom area rule and Whitcomb drag area rule based on equivalent cross-sectional area. It then establishes an efficient SST analysis and optimization approach from the perspective of coupling area rules. The approach demonstrates orders-of-magnitude efficiency advantage over computational fluid dynamics (CFD). Two optimization cases of a typical configuration delta wing body are implemented for verification. Equivalent cross-sectional areas are getting continuously smoother during the optimization. The fuselage optimization decreases maximum overpressure in far field by 13.45%, Perceived Level in Decibels (PLdB) by 1.7117 as well as drag coefficient by 6.72%. The full aircraft optimization yields 29.78% overpressure mitigation, 4.0798 PLdB reduction and 15.30% drag decrease. All results are validated by CFD and satisfy the analysis of coupled area rules. The cases indicate smoother cross-sectional area distribution facilitates sonic boom and drag mitigation simultaneously. Coupled area rules provide a novel view and efficient approach for SST design. The approach shows particular applicability in conceptual design with the advantage of high efficiency.