Q2. What is the method for creating the surface mesh?
It uses a top down meshing approach; the volume mesh is created first, and this is projected on to the faces and edges to generate the surface mesh.
Q3. How did the CFD model improve the airflow in the wind tunnel?
Adding the guide vanes to the wind tunnel upstream corners improved the airflow uniformity by 36% and combining upstream with downstream guide vanes improved the uniformity by 65%.
Q4. How much uniformity was obtained by adding the guide vanes to the wind tunnel upstream corners?
Adding the guide vanes to the wind tunnel upstream corners improved the airflow uniformity by 36 % and combining upstream with downstream guide vanes improved the uniformity by 65 %.
Q5. How did the addition of splitting plates reduce the velocity variations at diffuser exit?
The addition of splitting plates at the diffuser section effectively reduced the velocity variations at diffuser exit from 30 to 5%.
Q6. What was the result of the validation of the test section with the block model?
The validation of the test section with the block model showed that the CFD can generally reproduce the wind tunnel measurements of mean velocities, pressure coefficients and turbulent intensities with an error below 10%.
Q7. How much power is required to maintain steady flow through the tunnel?
The power required to maintain steady flow through the wind tunnel is equal to the total losses occurring in the flow through the tunnel.
Q8. Why did the air stream separate from the sides?
This was because of the separation of the air stream from the sides; an almost uniform low pressure wake was formed around the back surface.
Q9. What is the way to characterise wind tunnels?
Complete characterisation of wind tunnel test environment is a massive task due to the very extensive range of achievable configurations including scaled model testing.
Q10. How was the flow in the wind tunnel?
As expected, a more symmetric uniform flow was observed throughout the entire test section length and good overall airflow distribution in the wind tunnel circuit.
Q11. What was the effect of the flow field at the diffuser exit?
This was evident from the uniformity of the flow field at the diffuser exit (velocity variation was reduced from 30 % to 5% following the addition of horizontal and vertical splitting plates).
Q12. How was the average velocity in the test section reduced?
As expected, average velocity in the test section was reduced to 15.97 m/s following the integrationCirculations14of the guide vanes.
Q13. How many horizontal and 3 vertical splitting plates are installed inside the exit diffuser?
In order to avoid these occurrences, 3 horizontal splitting plates with 0.25 m spacing and 3 vertical splitting plates with 0.17 m spacing (14) are installed inside the exit diffuser.
Q14. What is the mesh resolution for the wall?
A very high mesh resolution was applied at the walls of the turning vanes at all four corners in order to increase the accuracy of capturing the flow passing through.