A concentric tube heat exchanger of length L = 1.5 m is used to thermally process a pharmaceutical product flowing at a mean velocity of um,c = 0.1 m/s with an inlet temperature of Ti = 20°C. The inner tube of diameter D, = 10 mm is thin walled, and the exterior of the outer tube (D, = 20 mm) is well insulated. Water flows in the annular region between the tubes at a mean velocity of Um.h = 0.2 m/s with an inlet temperature of Thi = 60°C. Properties of the pharmaceutical product are v = 10 × 10-6 m²/s, k = 0.25 W/m-K, p = 1100 kg/m³, and c, = 2460 J/kg-K. Evaluate water properties at T = 50°C. Hint: Entry effects for the pharmaceutical flow inside the tube can not be neglected. Use the Gnielinski correlation for turbulent flow of water in the annular region. Determine the value of the overall heat transfer coefficient U, in W/m².K. U = W/m².K Determine the mean outlet temperature of the pharmaceutical product when the exchanger operates in the counterflow mode, in °C. (Tc,o) counter °C Determine the mean outlet temperature of the pharmaceutical product when the exchanger operates in the parallel-flow mode, in °C. °C (Tc.o) parallel

A concentric tube heat exchanger of length L = 1.5 m is used to thermally process a pharmaceutical product flowing at a mean velocity of um,c = 0.1 m/s with an inlet temperature of Ti = 20°C. The inner tube of diameter D, = 10 mm is thin walled, and the exterior of the outer tube (D, = 20 mm) is well insulated. Water flows in the annular region between the tubes at a mean velocity of Um.h = 0.2 m/s with an inlet temperature of Thi = 60°C. Properties of the pharmaceutical product are v = 10 × 10-6 m²/s, k = 0.25 W/m-K, p = 1100 kg/m³, and c, = 2460 J/kg-K. Evaluate water properties at T = 50°C. Hint: Entry effects for the pharmaceutical flow inside the tube can not be neglected. Use the Gnielinski correlation for turbulent flow of water in the annular region. Determine the value of the overall heat transfer coefficient U, in W/m².K. U = W/m².K Determine the mean outlet temperature of the pharmaceutical product when the exchanger operates in the counterflow mode, in °C. (Tc,o) counter °C Determine the mean outlet temperature of the pharmaceutical product when the exchanger operates in the parallel-flow mode, in °C. °C (Tc.o) parallel

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.

Chapter10: Heat Exchangers

Section: Chapter Questions

Problem 10.46P

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