Laminar-Turbulent Flow in a Spherical Annulus

Experimental results are presented regarding the nature of the flow of a viscous incompressible fluid contained between two concentric spherical surfaces that rotate at different angular velocities. Depending upon the various parameters involved (the radius ratio, the angular velocity ratio, and the Reynolds number), the resulting flow in the spherical annulus may be laminar, turbulent, or some combination of laminar and turbulent flow. The basic laminar flow patterns are observed by use of flow visualization methods. Similarities and differences between the stability characteristics of spherical annulus flow and cylindrical annulus flow are discussed.