Control of three-dimensional separation due to sharp fins using co-rotating vanes ahead of quasi-conical and conical zones

This experimental investigation studies the effect of an array of 30 & DEG; inclined co-rotating vanes in controlling a three-dimensional interaction generated by a 15 & DEG; semi-infinite sharp fin at Mach 2.05. The array is located upstream of the quasi-conical and conical zones of interaction. The primary objective is to study variation in (i) vane chord length c/h = 7.2, 4.2, and 2.5 and (ii) vane height h/delta = 0.3, 0.5, and 0.75 for c/h = 2.5 case in controlling the interaction. Control with the smallest chord length of c/h = 2.5 and h/delta = 0.75 shows the most promising result relative to vanes with longer chord lengths. The vortex trails from this configuration penetrate deeply into the quasi-conical zone of interaction, thereby modifying it both azimuthally and radially. The plateau pressure in the conical region of interaction shows a reduction of approximately 60% with an accompanied reduction in the separation shock strength by nearly 70% for this case. Implementing control in either quasi-conical or conical zones reduces the overall control effectiveness considerably. Removing vanes ahead of quasi-conical zone reduces the effectiveness of favorably modifying the flow development in this region. The bow shock formed ahead of the first vane interacts with the three-dimensional interaction creating a pressure jump that separates the region of vortex influence from that of no control. Published under an exclusive license by AIP Publishing.

Automated summary

This experimental investigation examines the effect of an array of inclined co-rotating vanes on a three-dimensional interaction generated by a semi-infinite sharp fin. The study finds that using vanes with a smaller chord length and larger height can effectively control the interaction, reducing pressure and separation shock strength.