### 6.7.1. General Setup Guidelines

- CFX-Pre Turbomachinery Wizard:

  - When setting up your transient blade row problem, it is always recommended that you use the Turbomachinery wizard in CFX-Pre.

- Flow initialization:

  - A steady-state solution can be used as the initial condition for all transient flow simulations. You may use the Stage model (mixing-plane) or Frozen Rotor method, when modeling multiple blade rows.

- Time-integration:

  - For all transient blade row simulations, a uniform time step must be used.

  - You should not change the time step (number of time steps per period or timestep multiplier) in the middle of a simulation. However, you can stop a simulation, change the time step, then restart (continue) the simulation. For details, see Stopping and then Restarting Simulations with an Increased Number of Time Steps Per Period.

- Inflow and Outflow Boundary Conditions:

  - For proper comparison between the full domain solution and any of the transient blade row solutions, the inflow and outflow boundary conditions must be equivalent. For example: an average pressure specification on an outlet boundary should not apply on the full extent of the outlet in the full domain model but rather it should be applied to individual passage outlets to replicate the transient blade row solution boundary condition specification. Therefore it is advised to divide the full-domain inlet and outlet boundaries into multiple boundaries for each passage.

  - For an inlet disturbance problem: When working with profiles as boundary conditions, be sure to double-check the periodicity of the profiles on both reference test cases and the transient blade row test cases. You can use monitors at the inlet to do this check.

- Solution Monitoring:

  - You can use solution monitor points to monitor the results of the transient simulation.

  - When comparing the full-domain reference solution with the transient blade row solution, it is important to locate the monitors in the passages of the full-domain geometry with relative locations as in the transient blade row passage configuration.

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