I'm trying to solve what should be a very simple problem as part of a larger project I'm working on. It's just laminar flow in a pipe of length 14,000 feet and radius 0.04 feet. I'm just trying to find the steady-state solution for now. The issue is that the inlet velocity is satisfied on the boundary, but rapidly decays to zero velocity. This is demonstrated in the attached image.
It's a 2-D axisymmetric model. Symmetry on the left boundary, wall on the right, inlet at the top and outlet at the bottom. The outlet is set to a zero pressure, and I have tried many different inlet boundary conditions. I started with a much smaller system, the same radius, but a length of only 8 ft which worked perfectly, but it's not working on the larger system. I feel like I'm missing something obvious.
Thanks!
Kyle
It's a 2-D axisymmetric model. Symmetry on the left boundary, wall on the right, inlet at the top and outlet at the bottom. The outlet is set to a zero pressure, and I have tried many different inlet boundary conditions. I started with a much smaller system, the same radius, but a length of only 8 ft which worked perfectly, but it's not working on the larger system. I feel like I'm missing something obvious.
Thanks!
Kyle