عنوان مقاله [English]
In this paper, the interaction effects of the rotational flows on aerodynamic efficiency of propeller for a twin engine aircraft are investigated. Variable pitch propellers allow us to change the propeller pitch angle at different flight phase (i.e. take off, climb, cruise, and landing) and thus it change the pressure distribution and aerodynamic loads on a wing and horizontal stabilizer. Therefore, in the design process the integration of engine-propeller thrust with aircraft performance is an important subject. The aerodynamic coefficient is in the case of power-off engine and different than the case where the engine is powered-on. This difference, changes the trim conditions and aircraft controllability. In this work, to evaluate the change of aerodynamic coefficient, the computational fluid dynamic (CFD) in steady form is implemented accordingly, the comparisons are made for different speeds and flight conditions at different propeller pitch settings. The validation is therefore performed based on the comparison of simulated lift against the semi empirical data from wind tunnel test. Furthermore, the effects on aerodynamic coefficient, stability and control derivatives are analyzed.