Question

When immersed in a uniform stream, a thick elliptical cylinder (extending a width b into the picture) creates a broad downstream wake with a linear velocity profile having a centerline velocity of Ua=u. u:(9)=0- 4 + ) for Osysl and symmetry in the wake from top to bottom. The pressures at the upstream and downstream sections are approximately uniform and equal. a. Find an analytical expression for the drag force as a function of p, U.,L,b (width of cylinder into picture). In your solution, you need to work out the entire analysis starting with the conservation of mass and momentum equations from Lecture 19 Slide 5. Analytical solutions are given in fractions, not decimal approximations. b. Find the dimensionless drag coefficient, C, == 2F pUbL C. If the water flow has velocity U. = 4 m/s and the wake half-height is L=20 cm, estimate the drag force on the cylinder for a unit width into the paper. u=U 1:69)=v_[+ ]

Answer 1

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