Liquid mercury is being slowly heated for via a 8-m long tube as it flows at a rate of 0.3 kg/s. The tube has a rectangular cross-section of 4-cmx16-cm and supplies a uniform and constant heat flux of 1200 W/m2 to mercury. Mercury enters the tube at 10°C. Evaluate the properties of mercury at 50°C. (a) What is the thermal entry length? Comment if you can approximate the entire flow to be fully-developed. (b) What is the mean temperature of mercury at the outlet of the tube? Then justify if property evaluation at 50°C was a reasonable approximation. (c) What is the convection coefficient at the end of the tube? (d) What is the surface temperature at the end of the tube?

Liquid mercury is being slowly heated for via a 8-m long tube as it flows at a rate of 0.3 kg/s. The tube has a rectangular cross-section of 4-cmx16-cm and supplies a uniform and constant heat flux of 1200 W/m2 to mercury. Mercury enters the tube at 10°C. Evaluate the properties of mercury at 50°C. (a) What is the thermal entry length? Comment if you can approximate the entire flow to be fully-developed. (b) What is the mean temperature of mercury at the outlet of the tube? Then justify if property evaluation at 50°C was a reasonable approximation. (c) What is the convection coefficient at the end of the tube? (d) What is the surface temperature at the end of the tube?

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 7.13P

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