CFD-CSD Pre-test Hover Predictions Validation for the HVAB Rotor
Rohit Jain
Abstract
Pre-test hover predictions obtained for the 11.08-foot-diameter, 4-blade, Mach-scaled Hover Validation and Acoustic Baseline (HVAB) rotor were compared with the recent hover test measurements obtained in the National Full-Scale Aerodynamics Complex (NFAC) 80- by 120-Foot Wind Tunnel at NASA Ames Research Center. The predictions were obtained using high-fidelity Computational Fluid Dynamics (CFD)-Computational Structural Dynamics (CSD) coupled simulations in the CREATETM-AV Helios framework. Helios used NASA OVERFLOW and NASA FUN3D solvers for near-body CFD modeling and RCAS for CSD modeling. A comprehensive comparison was performed that included rotor performance, blade motions and deformations, laminar-turbulent transition location, airloads, surface pressure, and wake trajectory. Overall, the predictions agreed well with the test data.