9-63 Flow separates at a sharp corner along a wall and forms a recirculating separation bubble as sketched in Fig. P9-63 (streamlines are shown). The value of the stream function at the wall is zero, and that of the uppermost streamline shown is some positive value upper Discuss the value of the stream function inside the separation bubble. In particular, is it positive or negative? Why? Where in the flow is & a minimum? = upper = 0 Separation bubble FIGURE P9-63