Consider the flow conditions of Example 6.4 for two situations, one in which the flow is completely laminar, and the second for flow that is tripped to turbulence at the leading edge of the plate. Determine whether there is a plate length L for which the average convection coefficient for laminar flow is the same as the average convection coefficient for turbulent flow. Assume a water temperature of 300 K.

Example 6.4

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Water flows at a velocity u. = 1 m/s over a flat plate of length L = 0.6 m. Consider two cases, one for which the water temperature is approximately 300 K and the other for an approximate water temperature of 350 K. In the laminar and turbulent regions, experimental measurements show that the local convection coefficients are well described by ham(x) = ClamX-0.5 hurb(x) = Curb-X where x has units of m. At 300 K, while at 350 K, Clam,300 = 395 W/m¹.5. K Clam.350 = = 477 W/m¹.5. K Cturb.300 = 2330 W/m¹.8. K Cturb,350 = 3600 W/m ¹8. K