******************* This email originates from outside Imperial. Do not click on links and attachments unless you recognise the sender. If you trust the sender, add them to your safe senders list https://spam.ic.ac.uk/SpamConsole/Senders.aspx to disable email stamping for this address. ******************* Dear professor, I am new to Nektar++, and I want to know something about the CAA in Nektar++. I see the recent paper which use the Antares library solved the FWH equation, but the paper "Variations with Mach number for gust–airfoil interaction noise" is not using FWH euqation, does Nektar++ itself have the ability to calculate noise problem? If so, can the nosie problem only be calculated by compressible solver? If the noise problem cannot be calculated by a compressible solver alone, are we going to use an AcousticSolver? And why the Riemann solver in AcousticSolver maybe_unused? With best regards