P7.5 P7.5 A single-pass evaporator of a water chiller has 100 horizontal copper tubes of inner diameter 15mm and wall thickness 1.5mm through which water flows with a total mass flow rate of 1.8 kgs. Refrigerant 134a undergoes pool boiling at 2°C on the outer surface of the tubes. The water is cooled from 14°C to 6°C. The water-side and refrigerant-side heat transfer coefficients are 1100 Wm 2K and 980 Wm ²K¹ respectively. Calculate (i) the overall heat transfer coefficient based on the inner tube area, (ii) the LMTD (iii) the effectiveness of the evaporator, and (iv) the length of a tube. [Answers: (i) 567 Wm ²K¹, (ii) 7.28°C, (iii) 0.67, (iv) 3.13m]

P7.5 P7.5 A single-pass evaporator of a water chiller has 100 horizontal copper tubes of inner diameter 15mm and wall thickness 1.5mm through which water flows with a total mass flow rate of 1.8 kgs. Refrigerant 134a undergoes pool boiling at 2°C on the outer surface of the tubes. The water is cooled from 14°C to 6°C. The water-side and refrigerant-side heat transfer coefficients are 1100 Wm 2K and 980 Wm ²K¹ respectively. Calculate (i) the overall heat transfer coefficient based on the inner tube area, (ii) the LMTD (iii) the effectiveness of the evaporator, and (iv) the length of a tube. [Answers: (i) 567 Wm ²K¹, (ii) 7.28°C, (iii) 0.67, (iv) 3.13m]

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.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.53P

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