Aiming at the air intakes with different geometrical sections, the improved numerical simulation method is based on SST k-ω turbulence model is proposed, the internal flow field of three typical fuse air intakes with the uniform section straight, uniform section annular space and variable section trumpet are numerically simulated under the conditon of dissymmetrical subsonic flow with the attack angle.The flow pattern response of the dissymmetrical inflow in three air intakes are given, then the flow mechanisms are comparatively discussed. All those results show that the flow pattern response is caused of the low-viscous- incompressibleflow going into the three kinds of the intake is different. Then the flow slowing down effect for the niform section annular space was forecasted for different critical gap sizes. All of these give reference to the optimal design on gasdynamic distribution of fuze pneumatic generator.