Correlation of a Velocity Potential-Based Finite State Inflow Model with Experimental Data in Full and Inclined Ground Effect

A velocity potential-based finite state model (VPBFSM) has been developed to analyze an isolated rotor in ground effect. The model represents the ground using mass source distributions and imposes the non-penetration of flow boundary condition at the ground. In this paper, VPBFSM predictions of the inflow distribution are compared with experimental results for full and inclined ground effect cases using a model-scale rotor. The VPBFSM shows good agreement with the experimental results and captures the expected trend of decreasing inflow as the rotor approaches the ground, with a larger reduction on the side closest to the ground. Differences in magnitude are observed, but remain acceptable and are attributed to reduced-order modeling assumptions in the VPBFSM and uncertainty in the experimentally derived inflow measurements.