2. An exchanger is used to sub-cool a condensate from a methanol condenser from 95°C to 40°C. Flow rate of methanol 100,000 kg/h. Brackish water will be used as the coolant with a temperature rise from 25°C to 40°C. The exchanger has 300 tubes: 18mm in diameter and 20 m long. Determine the following: 1. The total surface area of the exchanger. 2. The Log Mean temperature Difference. 3. The overall heat transfer coefficient. 4. The heat duty, Q. 5. The temperature approach. 6. The cooling water flow rate in kg/s. Hints: Q=U A ATLMTD W Cph (T₁ - T₂) = w Cpc (t₂-t₁) Heat capacity of methanol = 2.84kJ/kg.°C. Heat capacity of water = 4.2 kJ/kg.°C.

2. An exchanger is used to sub-cool a condensate from a methanol condenser from 95°C to 40°C. Flow rate of methanol 100,000 kg/h. Brackish water will be used as the coolant with a temperature rise from 25°C to 40°C. The exchanger has 300 tubes: 18mm in diameter and 20 m long. Determine the following: 1. The total surface area of the exchanger. 2. The Log Mean temperature Difference. 3. The overall heat transfer coefficient. 4. The heat duty, Q. 5. The temperature approach. 6. The cooling water flow rate in kg/s. Hints: Q=U A ATLMTD W Cph (T₁ - T₂) = w Cpc (t₂-t₁) Heat capacity of methanol = 2.84kJ/kg.°C. Heat capacity of water = 4.2 kJ/kg.°C.

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.

Chapter9: Heat Transfer With Phase Change

Section: Chapter Questions

Problem 9.31P

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