This problem is for us to practice convection coefficient calculation for internal flow. You will have to design a water heating system that will heat up water flowing at 1 kg/s from 10°C to 40°C. You have to chose from two heated ducts - (a) one with rectangular cross-section of 0.6 mx1.2 m and (b) the other with 15 cm diameter circular pipe. Both ducts are maintained at a constant temperature of 60°C. Assuming that the flow is fully devloped in both cases, compare the length required for the two ducts to reach the deasired water temperature. Comment on whether the fully-developed assumption is justifiable in both cases.

This problem is for us to practice convection coefficient calculation for internal flow. You will have to design a water heating system that will heat up water flowing at 1 kg/s from 10°C to 40°C. You have to chose from two heated ducts - (a) one with rectangular cross-section of 0.6 mx1.2 m and (b) the other with 15 cm diameter circular pipe. Both ducts are maintained at a constant temperature of 60°C. Assuming that the flow is fully devloped in both cases, compare the length required for the two ducts to reach the deasired water temperature. Comment on whether the fully-developed assumption is justifiable in both cases.

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.67P: 1.67 In beauty salons and in homes, a ubiquitous device is the hairdryer. The front end of a typical...

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