申論題

Problem 6 (10 points) Blood is composed of plasma and blood cells. When blood flows through blood vessels with small diameters, the red cells are not uniformly distibuted across the vessel Iumen, but, instead, they are enriched in the central region of the blood vessel, and a thin cell- free layer is formed along the tube wall. Assuming that in each region the fow is considered to be Newtonian, the viscosities of the core region and the plasma layer are pe and Jo, respectively, the radius of the vessel is R and the thickness of the plasma layer is δ，