[newbie384]

Hi. I tried to simulate a turbine rotor with harmonic balance module with the following setup.

1) single rotor blade passage
2) Specifying the time-varying inlet total pressure and temperature with field function defined by extrapolating table data. In the stagnation inlet option, I enable the time-varying option and set the frequency. However, I do not know exactlyhow should I calculate the frequency f. Is it just f=1/Tpulse rad/s?
3) constant static pressure=0 at the outlet.
4) Use reference frame to model the rotor rotation.
5) Use grid-sequencing initialisation of a steady RANS solution as initial condition to harmonic balance.

With the above setup, my residual drops a bit initially and then it remain almost constant, and at some point floating point error occurs, which indicate divergence. I wonder whether the problem is caused by wrong setup (as described above) or my initial condition is not appropriate for pulsatile flow. I would very much appreciate if some experience people can advise on this.

Thank you in advance.