{"id":388738,"date":"2024-10-09T10:08:02","date_gmt":"2024-10-09T10:08:02","guid":{"rendered":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/fluent-runtime-dft-with-unsteady-boundary-condition\/"},"modified":"2024-10-09T10:08:02","modified_gmt":"2024-10-09T10:08:02","slug":"fluent-runtime-dft-with-unsteady-boundary-condition","status":"publish","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/fluent-runtime-dft-with-unsteady-boundary-condition\/","title":{"rendered":"Fluent – Runtime DFT with unsteady boundary condition"},"content":{"rendered":"

<p>Hi. I have a simulation where I want to utilise the Runtime DFT capabilities to give me Fourier coefficients in the domain for different discrete frequencies. I am using the single tone runtime DFT option for static pressure at a single frequency (for testing purposes). For reasons I’m not clear on, following sufficient run time, the DFT results are zero for both magnitude and phase. <\/p><p>I suspect this may be due to the fact that when I run the calculation, I have a boundary condition that updates at every time step (following each time step, a new pressure profile is defined at one boundary). Would this implementation be a reason that the Runtime DFT option would not work correctly? Surely, if the data is still in memory (i.e. the simulation isn’t closed during the runtime required), the DFT should still work. I’m wondering if anyone has any experience or suggestions?<\/p><p>Thanks in advance,<\/p><p>Joe<\/p><\/p>\n","protected":false},"template":"","class_list":["post-388738","topic","type-topic","status-publish","hentry","topic-tag-fluent","topic-tag-fluids","topic-tag-turbomachinery"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t