11.23 Chemical, civil, and mechanical engineers must often determine the power required to pump a fluid through a series of pipes. To do so, we must first determine a friction factor. If the fluid flow is turbulent and the pipes are smooth, the friction factor can be determined as 1.1513/vf = In (ReVf12.51) In this equation f represents the friction factor, a positive value that does not exceed 0.1, and Re represents the Reynolds number, which is a function of the fluid properties, the pipe diameter, and the nominal fluid velocity. The Reynolds number increases with increasing fluid velocity. The flow be- comes turbulent at higher velocities, when the Reynolds number exceeds approximately 3000. Hence the above equation is valid only when Re exceeds 3000. Determine the values of the friction factor corresponding to Reynolds numbers of 5000, 12,000, and 20,000. Does the friction factor increase or in decrease as the Reynolds number increases?

11.23 Chemical, civil, and mechanical engineers must often determine the power required to pump a fluid through a series of pipes. To do so, we must first determine a friction factor. If the fluid flow is turbulent and the pipes are smooth, the friction factor can be determined as 1.1513/vf = In (ReVf12.51) In this equation f represents the friction factor, a positive value that does not exceed 0.1, and Re represents the Reynolds number, which is a function of the fluid properties, the pipe diameter, and the nominal fluid velocity. The Reynolds number increases with increasing fluid velocity. The flow be- comes turbulent at higher velocities, when the Reynolds number exceeds approximately 3000. Hence the above equation is valid only when Re exceeds 3000. Determine the values of the friction factor corresponding to Reynolds numbers of 5000, 12,000, and 20,000. Does the friction factor increase or in decrease as the Reynolds number increases?

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.33P

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