عنوان مقاله [English]
This paper presents an upwind solution of compress ble inviscid fl.owfield around a helicopter rotor in hover, using Roe's scheme on unstruct ured tetrahe dral meshes. Higher order differences are computed using a high-order :Yionotone upstream Centered Conservat ion Law (MUSCL) method . The numer ical algorithm utilizes an explicit time integration scheme and the solution is accelerated by apply ing the implicit residual smoothing at every stage of time integrat ion. To demonstrate the solution aceuracy, the numerical simulations of the fl.owfield around an isolated helicopter rotor , in hover, for two operating conditions of subsonic and transonic tip vfach numbers of 0.44 and 0.877, with a blade pitch angle of 8 deg, are performed . The present results for aerodynamic characteristies, including the pres sure distributions at different sections of the blade, are compared with numerical and experimental re sults. The effec.ts of the spatial solution accuracy of the numerical method on the fl.owfield character istics and aerodynamic results of the rotor are also studied.