Broadband Noise Sources Acoustic Model CFD Simulation

Description

Broadband Noise Sources Acoustic Model, ANSYS Fluent CFD Simulation Training

Description

In this project, the airflow around a cylinder is simulated to investigate its acoustic condition using the Broadband noise sources model.

The two-dimensional geometry is designed in ANSYS Design Modeler software. Also, the structured grid is carried out using ANSYS Meshing meshing. As a result, 23264 elements were generated.

This CFD project is the 10th episode of the ANSYS Fluent General Training Course.

This product is the 4th episode of the Acoustic Model Training Course.

Methodology of Broadband Noise Sources Acoustic Model CFD Simulation

The simulation is Transient(unsteady) to capture fluid behavior over time. The Pressure-based solver type is used due to the incompressibility of the working fluid. Also, Broadband noise sources are employed.

Conclusion

The broadband noise sources model is the only one that allows us to display contour out of acoustics parameters. Thus, the related contours were extracted after the simulation to clearly show where the sound pressure level focused. The maximum acoustic power level contour is 8.74 W/m^3, which is very small compared to the dB produced. The reason is that very small acoustic pressures can produce very large disables. As it is clear from the acoustic power level contour, the highest amount of noise can be seen at the beginning of the back of the cylinder.

There are two other contours in the results of this simulation: LEE-Self noise X-source and LEE Shear-noise X-source. The LEE-Self noise X-source contour shows what the noise is due to the flow without the presence of the cylinder, and the LEE Shear-noise X-source shows what the number is for the condition where the cylinder obstruction is present. As it is clear, the number for the second case is much larger. This shows that most of the noise produced in this problem was due to the turbulent flow passing over the cylinder.