solution

Parallel flow of atmospheric air over a flat plate of length L 3 m is disrupted by an array of stationary rods placed in the flow path over the plate.

Laboratory measurements of the local convection coefficient at the surface of the plate are made for a prescribed value of u and Ts T. The results are correlated by an expression of the form hx  0.7 13.6x 3.4x 2 , where hx has units of and x is in meters. Evaluate the average convection coefficient for the entire plate and the ratio at the trailing edge.

For laminar flow over a flat plate, the local heat transfer coefficient hx is known to vary as x12 , where x is the distance from the leading edge (x 0) of the plate. What is the ratio of the average coefficient between the leading edge and some location x on the plate to the local coefficient at x?