6-1. Develop a momentum integral equation for steady flow without blowing or suction for use in the entry region of a circular tube. Note that Eq. (6-4) is not applicable for this case because it has been assumed that the boundary- layer thickness is small relative to the body radius R; in the present case the boundary layer ultimately grows to the centerline of the tube. -To 1/14 ( R ² pu² dy) = 1 d Rdx + Povou + - f (-p_u_-du-) dy dx u d R dx (Rpu dy) (6-4)