Numerical Simulation Of The Flow-field And Flow-noise Of Fully Appendage Submarine

The turbulence models RNGκ-ε, Realizableκ-ε,κ-ω,SSTκ-ωare all two-equation models and well known now. Combining these models with the RANS equation and the FW-H(The Ffowcs Williams and Hawkings Acoustic Model)respectively, the flow-noise of the water-drop shaped submarine model was calculated. And compared with the experimental results, we got the conclusion that for the computational model and conditions, the turbulence model RNG k -εcombined with RANS equation and the FW-H acoustic model can better simulate the resistance and flow-noise of the submarine compared with other turbulence models.Based on the work mentioned above, using the numerical method SIMPLE (Semi-Implicit Method for Pressure-Linked Equations) and the RNG k -εtwo-equation turbulence model, the three-dimensional viscous flow field of fully appendage submarine called DARPA SUBOFF was solved. Using the solution of viscous flow field , the FW-H (The Ffowcs Williams and Hawkings Acoustic Model)was added for the simulation of the unsteady flow-field and noise-field. The self-noise and radiated noise were calculated. And also the characteristics of flow noise around the submarine were analyzed. Based on these calculation and result validation, it can be concluded that the used method can simulate the flow-field as well as the flow-noise correctly.Then the flow field and flow noise of bare hull, sail appendage, stern appendages, and fully appended submarine models of DARPA SUBOFF were calculated in detail. By the comparison and analysis of the results, the influence to the flow field and flow noise of the submarine's appendage was clarified.At last we compared the difference of the flow field and flow noise between the X stern and the traditional stern models, found that the difference was not so distinct.