Advances in Rotorcraft Simulations With Unstructured CFD

Advances have been made in the development of unstructured solver methods suitable for fixed wing analyses, as well as rotary-wing applications, including interaction aerodynamics. This paper demonstrates the ability of an unstructured overset solver, FUN3D, to resolve the viscous compressible equations of motion for rotor-fuselage interactions and rotor-alone configurations. The solver is capable of modeling fully-articulated rotors (prior work was limited to rotation and flapping) and CFD-CSD loosely-coupled solutions including trim, using overset approaches. Initial results with the UH60A rotor indicate that the unstructured solver provides similar loading to its structured solver counterparts. Additional development of efficient domain connectivity interface routines are warranted to provide the ability to perform tightly-coupled rotor simulations.