Based on the computational fluid dynamics (CFD) technique

a twodimensional model was adopted to carry out the simulation. A method to identify combined dynamic derivative was developed and testified with small amplitude oscillation

then three computational models: the model with intake and exhaust effect

the model with ventilating effect and traditional fairing model

were built

furthermore the stable and dynamic aerodynamics of the models was numerically simulated

and the dynamic derivatives were also calculated. Results and their analysis indicate that the method to obtain dynamic derivative is reliable

and compared with faring model

the stable stall angles of attack (AOAs) of the other two models are bigger with increasing lift

drag and pitching moment coefficients

however

the slopes of pitching moment coefficient are almost the same

showing there is no clear difference of static stabilities among the models. Moreover

the absolute value of dynamic derivative of intake and exhaust models is the largest for all the models at the same AOA

showing this model has the largest dynamic damping

the model with ventilating effect takes the second place and the fairing model has the minimum value.