Measurements, visualization and interpretation of 3-D flowsapplication within base flows

Experimental investigations of the flow field in the near-wake of axisymmetric afterbodies at an angle of attack of 5° are reported. Models consists of a cylindrical afterbody and a conical boat tail. Measurements were performed by means of a 3-D frequency-shifted laser Doppler velocimeter at a free stream Mach number of 0.5. The tremendous increase of quantitative information obtained with this diagnostic technique raises the problem of reducing and displaying the data in a way that avoids large amounts of numbers and curves that are not easy to interpret. An attempt is made to visualize and to describe velocity characteristics in the form of a 3-D graphic representation