03.1 - Aerodynamics – CFD Methods and Validation
PARELLEL UNSTEADY REYNOLDS-AVERAGED NAVIER-STOKES (URANS) STUDEIS OF THE PERFORMANCE OF ONR WATERJET AXWJ-2
S.E. Monroe, Clarkson University, United States
The accuracy of SimericsMP+ Unsteady Reynolds-Averaged Navier-Stokes (URANS) is validated by studying turbulent flow past counter rotating propellers (CRPs). Subsequently, URANS is used to study an axial flow in an Office of Naval Research (ONR) waterjet and the pump’s performance. Specifically, experimental data from Miller (1976) as well as LES results from Hu et al (2019) are employed to compare against the current URANS results. Due to the large size of 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 pump, torque and head coefficients are plotted for a range of flow rates. For both studies, two different mesh sizes were utilized. The finer meshes of both studies contained roughly twice the number of cells found in their respective coarse meshes. These refinements lead to minor improvements, showing good convergence. The URANS torque and thrust coefficients were 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 pump displayed even better agreement, with the greatest error across all flow conditions remaining under 3%.