Hi all, I'm studying 3D devlopement of jets and am using a 3D1D setup with Fourier coefficients in the spanwise directions. Instead of starting a 3D1D case from scratch (the mesh contains 32 million DOF in 3D) I was thinking of trying out a few strategies in order to speed up convergence. I have tried out the steady-state module but it seems to take a rather long time to converge as well. I was thinking therefore, whether it would be possible to start the case in 2D, and once it reaches convergence, to switch over to a 3D 1D mode using a 2D .chk file as a restart point. I have tried out a few cases with the procedure described above, but cases always seem to blow up after restarting in the 3D 1D mode. I could explore the parameter space by reducing the time-step or number of expansion modes etc, but I'd like to know if there is a fundamental block to this kind of approach, or indeed if there are better approaches to speeding up convergence. Sincerely, -- *Amitvikram Dutta* Graduate Research Assistant Fluid Mechanics Research Lab Multi-Physics Interaction Lab University of Waterloo