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Rotor Loads Prediction Using Helios: A Multisolver Framework for Rotorcraft Aeromechanics Analysis

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This paper documents the prediction of UH-60A Black Hawk aerodynamic loading using the multisolver Computational Fluid Dynamics/Computational Structural Dynamics analysis framework for rotorcraft Helios for a range of critical steady forward flight conditions. Comparisons with available flight test data are provided for all of the predictions. The Helios framework combines multiple solvers and multiple grid paradigms (unstructured and adaptive Cartesian) such that the advantages of each paradigm is preserved. Further, the software is highly automated for execution and designed in a modular fashion to minimize the burden on both the users and developers. The technical approach presented herein provides details of all of the participant modules and the interfaces used for their integration into the software framework. The results composed of sectional aerodynamic loading and wake visualizations are presented. Solution-based adapative mesh refinement, a salient feature of the Helios framework, is explored for all flight conditions and comparisons are provided for both aerodynamic loading and vortex wake structure with and without adaptive mesh refinement.


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