I'm using Ansys Fluent 17.0 and trying to calculate a pressure surge in a shock tube.
The tube is 10 mm in diameter, the driver is 1000 mm and the driven is 200 mm long. I'm using the desinty-based-solver and the Material is oxygen as ideal gas.
During the calculation I have the problem that in later time steps the residuals only fall during the first 5 iterations and remain almost constant afterwards.
can someone tell me what my mistake is?