View Issue Details
|ID||Project||Category||View Status||Date Submitted||Last Update|
|0000885||OpenFOAM||[All Projects] Bug||public||2013-06-11 16:48||2015-02-24 17:00|
|Priority||high||Severity||major||Reproducibility||have not tried|
|Fixed in Version|
|Summary||0000885: RotorDiskSource affected by cylindricalCS bug previously reported 2012-12-21 and other specific bug|
|Description||The new source implemented into Openfoam "RotorDisk" accept as true that correct cylindrical transformation is applied over vector fields using cylindricalCS tool. |
That transformation is valid for points but not for vector fields.
Apart from that bug already known, this source is "valid" only for propellers but not for wind turbines.
|Steps To Reproduce||Wind Turbine modelled|
|Additional Information||vector localForce = vector(0.0, -f*Cd, tipFactor*f*Cl); //ORIGINAL|
It is needed to project Cd and Cl ( obtained from polar curves) taking into account the angle of attack "alphaEff". When alphaEff is too small, the cosine is almost one and the approximation may be valid. In the case of helicopters for example the major force contribution is normal to the rotor plane, but when dealing with windmill, it is needed to take into account also the swirl due to the lift component.
So if I am correct:
-f*Cd ====> -f*Cd*cos(alphaEff)+tipFactor*f*Cl*sin(alphaEff)
|2015-02-14 21:36||wyldckat||Tag Attached: cylindricalCS|
|2015-02-14 21:41||wyldckat||Note Added: 0003773|
|2015-02-24 16:59||henry||Note Added: 0003887|
|2015-02-24 16:59||henry||Status||new => resolved|
|2015-02-24 16:59||henry||Resolution||open => fixed|
|2015-02-24 16:59||henry||Assigned To||=> henry|