Authors: Sebastien Lachance-Barrett (Cornell University) & Edwin Corona (University of Waterloo)
Problem Specification
1. Pre-Analysis & Start-Up
2. Geometry
3. Mesh
4. Physics Setup
5. Numerical Solution
6. Numerical Results
7. Verification & Validation
Numerical Solution
Here, we tell FLUENT which solution method to use, how many iterations to perform, how to initialize to solution and what to visualize during the calculation. Finally, we run the calculation.
Summary of steps in the above video:
- Solution Methods
- Change Scheme to Coupled
- Pressure to Standard
- Check Pseudo Transient and High Order term relaxation
- Monitors
- Change the residuals of each field to 1e-6
- Create a surface monitor
- Select plot
- Select write
- Select Blade surface
- Solution Initialization
- Standard
- From inlet
- Standard
- Run Calculation
- Set the number of iterations to 1500
- Initialize and Run calculation
Note
In the above video we set the residuals to be very small, at 1e-6. This effectively ensured that the calculation did not stop before before the 1500 iterations specified. A solution is deemed to have converged (and the calculation ends) when ALL residuals fall below the limit set. Although I forgot to input 1e-6 for k and omega, the outcome is the same because the x-velocity, y-velocity and z-velocity residuals had not reached 1e-6.
For the first few hundred iterations you may see "reversed flow" being listed with each iteration. This will eventually disappear as the solution stabilizes and is nothing to be concerned over. This can easily be fixed in later iterations by moving the outlet further away from the wind turbine blade geometry.
Solving may take a while depending on your computer and how it is set up, to give you an idea of the time it might take some run times are listed below.
Computer Specs | Configuration | Run Time |
---|---|---|
Intel i7-4770S quad core 3.10 GHz 16 GB RAM (Phillips Lab at Cornell University) | Double Precision 2 Parallel Processes | 67 minutes |
intel i7 - 2600 quad core 3.40 GHz 16 GB RAM (Upson Lab at Cornell University) | Double Precision 2 Parallel Processes | 75 minutes |