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Title: Parallel Unsteady Reynolds-Averaged Navier-Stokes (URANS) Studies of the Performance of ONR Waterjet AxWJ-2
The accuracy of SimericsMP+ Unsteady Reynolds-Averaged Navier-Stokes (URANS) model is validated by studying turbulent flow past counter-rotating propellers (CRPs). Subsequently, URANS is used to study the axial flow in an Office of Naval Research (ONR) waterjet and its performance. Specifically, experimental data from Miller (1976) is employed for comparison against the URANS results. Due to the large number of degrees of freedom for both simulations, parallel computing over 80 cores is involved. For the CRP study, torque and thrust coefficients are plotted against a range of advance ratios, ensuring a Reynolds number of less than 500,000. For the waterjet, torque and head coefficients are plotted for a range of flow rates at a Reynolds number of 1.25 × 106. For both studies, two different mesh resolutions are utilized. The finer meshes of both studies contained roughly four times the total number of cells found in their respective coarse meshes. These refinements lead to minor improvements, showing good convergence. The URANS torque and thrust coefficients are found to be within 10% of that from experimental data across all advance ratios for the CRP set, showing good agreement. The torque and head coefficients for the waterjet displayed even better agreement, with the greatest error across all flow conditions remaining under 3%. It is concluded that the stator is responsible for 20% of the waterjets power production.  more » « less
Award ID(s):
1852102
NSF-PAR ID:
10414214
Author(s) / Creator(s):
Date Published:
Journal Name:
AIAA Region I Conference, March 2023
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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