Yes of course! Since posting the question I have made amendments (namely changing the anechoic layer from compressible to incompressible) and this is the result I get:nHowever, this is the absorption coefficient graph realised in the literature:nAs you can see the behaviour displayed by my model is completely different. I have used the same material parameters, and have used the same equation to calculate the impedance for 100 values between 0-3500 Hz. Little other information about how the structure was actually modelled is given in the paper, though I think one big difference may be the wave speed used. I have used a value of 50.3 m/s for the speed in the silicon layer- they haven't stated what was used during simulation but the wave speed used to calculate impedance in both their and my model is 325(1+0.11i). As far as I am aware there is no way to input a complex number for wave speed in ANSYS. nI am not sure how to amend my model, though it is clearly incorrect. Any help is greatly appreciated.nThank you, Callum.n(Reference: Xinyi Fu, Zhongkun Jin, Yao Yin, and Bilong Liu, 'Sound absorption of a rib-stiffened plate covered by anechoic coatings'.)n