70 3. A radial-flow channel has been developed to measure the adhesion (energy) of cells to surfaces in vitro. The radial-flow channel is shown in the figure below. In this device, fluid flows in from a central source, flows out in a radial direction and the volumetric flow rate at any positions r is Q. The flow itself is driven by an unspecified pressure gradient. a) Solve for the velocity profile (10 pts). b) Use your solution for the velocity profile and the constant flow rate condition to show that the wall shear stress at y h/2 is given by 76 y " 2 3 μο T Val V₁₂-0 лrh² P Ay V₁TO 心: Tyrlysty h 12