Hello, I have an enclosed volume with a fluid inside. And I have to apply an Acceleration PSD to it. So: 1) I am using MFLUID with VMOPT 2 in order to obtain a good modal base for my analysis. 2) To simulate the pressure, I am using a PLOAD4. I've made several tests for this Analysis to work, but my RMS Von Mises is incredibly high. I tested: 1) Normal Modes of the Structure with and without MFLUID: all is OK and I can see a reduction of the Frequency. 2) Modal Frequency Response without MFLUID is OK: the RMS values are pretty low - around 4-6 MPa. 3) BUT the Modal Frequency Response with MFLUID gives me HUGE RMS values. 4) I checked the Eigenvector Values of the Normal Modes Analysis - with and without MFLUID. The analysis with MFLUID has numbers around 1000 times higher. Question: is there some way of obtaining a good Modal Base for a Modal Response Analysis, by using the MFLUID card?