Impact of variant attack of angle on the unsteady pressure fluctuation characteristics of the flow over slender body

Tests of sharp ogive nose cylinders at variant angle of attack with smoke visualization and pressure fluctuation measurement have been carried out in subcritical Reynolds number region. As the angle of attack α increasing from 0° to 90°, there are four kinds of vortices structure and they are attaching flow structure, twin vortices structure, asymmetric vortices structure and mixed vortices structure in turn. The pressure fluctuation magnitude alone the axis is unchanged in attaching flow structure and twin vortices structure, increasing in asymmetric vortices structure, and decreasing in mixed vortices structure. The pressure fluctuation frequency alone the axis is decreasing in asymmetric vortices structure, and increasing in mixed vortices structure.