Obtain by dimensional analysis a functional relationship for the wallheat transfer coefficient h (W/m2-K) for a fluid flowing through astraight pipe of circular cross section. Assume that the effects ofnatural convection may be neglected in comparison with those offorced convection. Taking the heat transfer coefficient, h, as afunction of the fluid velocity, density, viscosity specific heat andthermal conductivity, v, p, H, Cp and k, respectively, and of the insidediameter of the pipe, d. For recurring set, the variables d, u, k, and p. Itfound by experiment that, when the flow is turbulent, increasing theflowrate by a factor of 2 always results in a 60 percent increase in thecoefficient. How would a 50 percent increase in density of the fluid beexpected to affect coefficient, all other variables remaining constant?

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Obtain by dimensional analysis a functional relationship for the wall heat transfer coefficient h (W/m2-K) for a fluid flowing through a straight pipe of circular cross section. Assume that the effects of natural convection may be neglected in comparison with those of forced convection. Taking the heat transfer coefficient, h, as a function of the fluid velocity, density, viscosity specific heat and thermal conductivity, v, p, µ, Cp and k, respectively, and of the inside diameter of the pipe, d. For recurring set, the variables d, u, k, and p. It found by experiment that, when the flow is turbulent, increasing the flowrate by a factor of 2 always results in a 60 percent increase in the coefficient. How would a 50 percent increase in density of the fluid be expected to affect coefficient, all other variables remaining constant?

Obtain by dimensional analysis a functional relationship for the wall heat transfer coefficient h (W/m2-K) for a fluid flowing through a straight pipe of circular cross section. Assume that the effects of natural convection may be neglected in comparison with those of forced convection. Taking the heat transfer coefficient, h, as a function of the fluid velocity, density, viscosity specific heat and thermal conductivity, v, p, µ, Cp and k, respectively, and of the inside diameter of the pipe, d. For recurring set, the variables d, u, k, and p. It found by experiment that, when the flow is turbulent, increasing the flowrate by a factor of 2 always results in a 60 percent increase in the coefficient. How would a 50 percent increase in density of the fluid be expected to affect coefficient, all other variables remaining constant?

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.54P

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