11-75 PtD | Consider a shell and tube heat exchanger in a milk pasteurizing unit in which the milk flowing is to be heated from 20°C by hot water initially at 140°C and flow- ing at a rate of 5 kg/s. The milk flows through 30 thin-walled tubes with an inside diameter of 20 mm with each tube making 10 passes through the shell. The average convective heat trans- fer coefficients on the milk and water side are 450 W/m²-K and 1100 W/m²-K, respectively. In order to complete the pasteur- izing process and hence restrict the microbial growth in the milk, it is required to have the exit temperature of milk attain at least 70°C. As a design engineer, your job is to decide upon the shell width (tube length in each pass) so that the milk exit temperature of 70°C can be achieved. One of the design requirements is that the exit temperature of hot water should be at least 10°C higher than the exit temperature of milk.

11-75 PtD | Consider a shell and tube heat exchanger in a milk pasteurizing unit in which the milk flowing is to be heated from 20°C by hot water initially at 140°C and flow- ing at a rate of 5 kg/s. The milk flows through 30 thin-walled tubes with an inside diameter of 20 mm with each tube making 10 passes through the shell. The average convective heat trans- fer coefficients on the milk and water side are 450 W/m²-K and 1100 W/m²-K, respectively. In order to complete the pasteur- izing process and hence restrict the microbial growth in the milk, it is required to have the exit temperature of milk attain at least 70°C. As a design engineer, your job is to decide upon the shell width (tube length in each pass) so that the milk exit temperature of 70°C can be achieved. One of the design requirements is that the exit temperature of hot water should be at least 10°C higher than the exit temperature of milk.

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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