A long, thin-walled double-pipe heat exchanger with tube and shell diameters of 0.01 m and 0.025m, respectively, is used to condense refrigerant-134a with water at 20°C. The refrigerant flowsthrough the tube, with a convection heat transfer coefficient of hi= 4100 W/m² °C. Water flowsthrough the shell at a rate of 0.3 kg/s. The thermal resistance of the inner tube is negligible sincethe tube material is highly conductive and its thickness is negligible. Both the water andrefrigerant-134a flows are fully developed. Properties of the water and refrigerant-134a areconstant.Water properties: p = 998 kg/m³, v=u/p-1.004x 10-6 m²/s, k = 0.598 W/m. °C, Pr = 7.01Cold waterDDo Question Completion Status:QClick Save and Submit to save and submit. Click Save All Answers to save all answers.MIPart b:Limestone layera) Determine the overall heat transfer coefficient (W/m². °C) of this heat exchanger (assume nofouling).@b) Determine the overall heat transfer coefficient (W/m². °C) of this heat exchanger, assume thereis fouling. A 2-mm-thick layer of limestone (k = 1.3 W/m °C) forms on the outer surface of theinner tube. The limestone layer can be treated as a plain wall layer since its thickness is verysmall relative to its diameter.23E$4R%5zdT^6MacBook ProY&7C+0081(Cold water-S9D.0OODoHot R-134aSave All AnswersPSave and Submit4

Given: The diameter of the tube→Di=0.01 m The diameter of the outer shell→Do=0.025 m The convective…

Cold water D₁ Do Hot R-134a Part b:Limestone layer a) Determine the overall heat transfer coefficient (W/m². °C) of this heat exchanger (assume no fouling). b) Determine the overall heat transfer coefficient (W/m². °C) of this heat exchanger, assume there is fouling. A 2-mm-thick layer of limestone (k = 1.3 W/m °C) forms on the outer surface of the inner tube. The limestone layer can be treated as a plain wall layer since its thickness is very small relative to its diameter.

Cold water D₁ Do Hot R-134a Part b:Limestone layer a) Determine the overall heat transfer coefficient (W/m². °C) of this heat exchanger (assume no fouling). b) Determine the overall heat transfer coefficient (W/m². °C) of this heat exchanger, assume there is fouling. A 2-mm-thick layer of limestone (k = 1.3 W/m °C) forms on the outer surface of the inner tube. The limestone layer can be treated as a plain wall layer since its thickness is very small relative to its diameter.

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 7.14P

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