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NASA NTRS · 20220005496

Application of Rotor Disk Model in the Overflow CFD Code

Jasim U. Ahmad
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Abstract

To reduce the complexity and to reduce the cost of turnaround time of simulating unsteady flows of rotating blades with moving overset grids, amid-fidelity option is provided in the OVERFLOW computational fluid dynamics analysis to model rotors and propellers as infinitely thin disks. The effect of the flow through the disk is represented by the momentum source terms in the governing Navier-Stokes equations. The model is loosely coupled with the rotorcraft comprehensive analysis CAMRADII. A brief description of the coupling algorithm is provided. Simulations of a single rotor and multiple rotors are shown, including comparisons with measurements and with the full rotor where all blades are modeled, and unsteady simulation performed with moving grids for rotating geometry,

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Jasim U. Ahmad. 2022-04-16. Application of Rotor Disk Model in the Overflow CFD Code. https://ntrs.nasa.gov/citations/20220005496

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