8.21 WP In the final stages of production, a pharmaceutical is sterilized by heating it from 25 to 75°C as it moves at o.2 m/s through a straight thin- walled stainless steel tube of 12.7-mm diameter. A uniform heat flux is maintained by an electric resistance heater wrapped around the outer surface of the tube. If the tube is 10 m long, what is the required heat flux? If fluid enters the tube with a fully developed velocity profile and a uniform temperature profile, what is the surface temperature at the tube exit and at a distance of o.5 m from the entrance? Fluid properties may be approximated as p = 1000 kg/m3, c, = 4000 J/kg · K, µ = 2 × 103 kg/s · m, k = o.8 W/m · K, and Pr = 10.

8.21 WP In the final stages of production, a pharmaceutical is sterilized by heating it from 25 to 75°C as it moves at o.2 m/s through a straight thin- walled stainless steel tube of 12.7-mm diameter. A uniform heat flux is maintained by an electric resistance heater wrapped around the outer surface of the tube. If the tube is 10 m long, what is the required heat flux? If fluid enters the tube with a fully developed velocity profile and a uniform temperature profile, what is the surface temperature at the tube exit and at a distance of o.5 m from the entrance? Fluid properties may be approximated as p = 1000 kg/m3, c, = 4000 J/kg · K, µ = 2 × 103 kg/s · m, k = o.8 W/m · K, and Pr = 10.

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 7.19P

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