Analysis On Aerodynamic Interactions Of Helicopter Rotor/Fuselage/Empennage Based On CFD

The simulation of the interference flow field of the rotor/fuselage/empennage is a significant andchallenging task in the helicopter aerodynamics，which plays an essential role in modern helicopter’sdesign and development. To investigate the characteristics of the interference flow field, this thesisestablished a CFD method based on the momentum source theory with the Euler equations andcoupled with a rotor trim model. By using this method, the aerodynamic characteristics of the rotor/fuselage/empennage are calculated. Particularly, we have focused on investigating the fuselage’ssurface pressure influenced by the rotor, the rotor performance influenced by the fuselage, and theaerodynamic characteristics between the rotor and empennage. The major research in the thesis is asfollows:In Chapter1, the significance of investigating the interference flow field of the rotor/fuselage/empennage as well as the research at home and abroad are introduced as the background andpremise. Finally, the necessity of coupling with a rotor trim model in CFD method to investigate thissubject is pointed outIn Chapter2, several types of the mesh are compared. Then the ROBIN and MARYLAND modelare taken as the research’s object. A method for generating the mesh which used to calculate theinterference flow field of the rotor/fuselage/empennage is established.In Chapter3, a rotor trim model which suit for the CFD calculation is established. By researchingthe CFD numerical simulation and the rotor momentum source model, a method with a goodcomputational efficiency to calculate the interference flow field of the rotor/fuselage/empennage isdeveloped, and the calculator program is finished. Meanwhile, the result of the calculation which withand without the rotor trim model are compared. It is proved that the method is useful.In Chapter4, by using the method established above, the characteristics of the rotor/fuselageinterference flow field which under the hover and forward flight state were calculated respectively.Then the interference flow field which under different forward flight speeds and thrust coefficients arecompared and analyzed, Finally some useful results are summarized.In Chapter5, the interference flow field of the rotor/empennage is simulated with different forwardflight speeds and the empennage parameters. Then some meaningful conclusions are summarized.