Task 2A heat exchanger that is used for cooling lubricating oil is comprised of a thin-walled inner tube of 30mm diameter carrying water and an outer tube of 50 mm diameter carrying the oil. The exchangeroperates in counterflow mode with an overall heat transfer coefficient of 65 W/m² K and the tabulatedaverage properties are given.PropertiesP (kg/m²)(J/kg-K)▸ (m²/s)k (W/m K)PrPage 6 of 8Water100042007 x 1070.644.7Oil80019001 x 10-50.134140Join = 100°cOiLm = 0.2kg/sTo, outtrWater>mw=0-15kg,STwin =LTw, out30°℃(a) If the outlet temperature of the oil is 60°C, determine the total heat transfer and the outlettemperature of the water.(b) How long must the tube be made if the outlet temperature of the oil is 60°C?(c) Explain and discuss with the use of diagrams the difference between parallel and counter flow heatexchangers?(d)If the heat exchanger is changed to a parallel flow heat exchanger, how long must the tube be madeif the outlet temperature of the oil is 60°C?

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Task 2 A heat exchanger that is used for cooling lubricating oil is comprised of a thin-walled inner tube of 30 mm diameter carrying water and an outer tube of 50 mm diameter carrying the oil. The exchanger operates in counterflow mode with an overall heat transfer coefficient of 65 W/m² K and the tabulated average properties are given. Properties p (kg/m³) (J/kg-K) (m²/s) k (W/m .K) Pr Page 6 of 8 Water 1000 4200 7 x 10-7 Water> 0.15 kg, 0.64 4.7 To, out Oil 800 1900 1x 10-³ 0.134 140 To, in = 100°c KOIL m = 0.2kg/s

Task 2 A heat exchanger that is used for cooling lubricating oil is comprised of a thin-walled inner tube of 30 mm diameter carrying water and an outer tube of 50 mm diameter carrying the oil. The exchanger operates in counterflow mode with an overall heat transfer coefficient of 65 W/m² K and the tabulated average properties are given. Properties p (kg/m³) (J/kg-K) (m²/s) k (W/m .K) Pr Page 6 of 8 Water 1000 4200 7 x 10-7 Water> 0.15 kg, 0.64 4.7 To, out Oil 800 1900 1x 10-³ 0.134 140 To, in = 100°c KOIL m = 0.2kg/s

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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