sonny cain


I am wanting to increase surface roughness from 0.0001m to 0.001m and analyse the lift and drag coefficient for each Surface Roughness. I set up a Boundary Condition on the edge which the surface roughness must change, right clicked and set this as an input parameter then chose Lift and Drag as my output parameters. 

If I leave it to run, the first parameter provides a correct value, but then it gives the same lift and drag value for each surface roughness after that which is incorrect. 

My thoughts are because the lift and drag is from a plot which must converge, the plot isnt being reset between changing the surface roughness which is causing the same lift and drag coefficient.