## Search found 5 matches

Thu Jan 31, 2019 4:16 pm
Forum: Controls
Topic: questions about reference control input
Replies: 61
Views: 15637

### Re: questions about reference control input

Dear Cheng, Yes, the structural DOFs can impact the performance of the controller. The pitch angle can be negative, depending on definition of aerodynamic twist (the sum of the pitch + twist angles equals the angle between the chord and rotor plane). The twist is often defined such that "optim...
Thu Nov 29, 2018 9:56 am
Forum: Structural Analysis
Topic: Mass matrix Theoretical calculations of Blade
Replies: 5
Views: 1968

### Re: Mass matrix Theoretical calculations of Blade

Dear Jason,
Thanks for your suggestions and also discussion in "Definition of Parameters" helped a lot.
Thank you
Thu Nov 29, 2018 6:15 am
Forum: Structural Analysis
Topic: Mass matrix Theoretical calculations of Blade
Replies: 5
Views: 1968

### Re: Mass matrix Theoretical calculations of Blade

Dear Jason, I am unable to attach the 4th image so I am writing separately, rotation.PNG how the beta(rotation) is taken, it is shown in the figure but there is no particular explanation. can you explain in detail or provide any reference. Sir, I need the data of any regular airfoil just for testing...
Thu Nov 29, 2018 6:04 am
Forum: Structural Analysis
Topic: Mass matrix Theoretical calculations of Blade
Replies: 5
Views: 1968

### Re: Mass matrix Theoretical calculations of Blade

massmatrix.PNG where R is the vector in reference configuration, ui(R, t) = Φ(R)q(t) is displacement field vector, Φ(R) is the assumption function. we can derive corresponding approach functions ϕ_i (x),ϕ_j (x) and ϕ_t (x). assum.PNG where rcos(phi) and rsin(phi) are the polar coordinates of the el...
Wed Nov 28, 2018 4:12 pm
Forum: Structural Analysis
Topic: Mass matrix Theoretical calculations of Blade
Replies: 5
Views: 1968

### Mass matrix Theoretical calculations of Blade

Dear Jason, I am trying to calculate Mass matrix of a rotor blade ultimately to find the bending and torsional modes. If I consider blade as Ellipse then the polar coordinates will be (x,r cos[phi], r sin [phi]). But my professor suggested me to consider it as an airfoil. Is it possible to take the ...