  With technological advancements in autonomous aerial systems, Micro Aerial
Vehicles (MAVs) have increased applications due to their small size, better
maneuverability, and remote operability. Non-conventional designs, such as
closed box-wing structures, have reduced induced drag, enabling a higher
payload capacity, endurance, and aerodynamic efficiency. Current studies have
widely studied the applicability of box-wing for large commercial aircraft,
general aviation, and medium to large UAVs. Despite the increased work on
non-conventional wing aircraft, little has been studied about the applicability
of box-wing design over a monoplane in the MAV scale and the choice of
parameters that enable the box wing to be best suited. This work presents
numerical simulation results for box-wing configurations in contrast with the
conventional monowing design, considering operations at lower Reynolds numbers
and aspect ratios suitable for small UAV operations. We study the effects of
lift, skin friction, and induced drag along with aerodynamic efficiency for six
structures. It is intuitive to expect that the decreased induced drag would
prove the box-wing design outperformed the conventional design. However, the
additional parasitic drag generated makes the monowing model a slightly better
choice. The simulations reveal that the box-wing lowers induced drag by 2 to
12% compared to a monowing aircraft but produces a lesser total lift to drag
ratio by 10% at equal lift requirement. Our analysis also addresses the effect
of varying aspect ratios and Reynolds numbers on the simulation results for the
box-wing and monowing designs and discusses the suitability of choosing a
particular structure based on mission requirements.
