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Ansys Learning Forum Forums Discuss Simulation Fluids Aeroacoustics – Negative Decibels Reply To: Aeroacoustics – Negative Decibels

Federico
Ansys Employee

Hello Jack, 

negative Sound Pressure Level indicates that the pressure fluctuations being simulated are lower than the reference pressure used to calculate SPL, so your results would suggest that you may not be resolving those pressure fluctuations. 

Are you using the same mesh and time step size for both cases?