A new rotor computational fluid dynamics(CFD)/comprehensive analysis (CA) loose coupling model is presented in this paper. In the coupled analysis, moderate deflection beam theory is employed to obtain the blade motions, while a high fidelity, overset grid based N-S solver is adopted to compute airloads. In order to improve the computation efficiency, the delta method is used to integrate the airloads computed by CFD analysis into the CA module. Based on the aforementioned method, the airloads at two challenging level-flight conditions of the UH-60A Blackhawk helicopter are investigated, and the simulated results show that the CFD/CA coupling model developed in this paper is efficient and accurate in capturing the rotor unsteady airloads.
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