In a food processing plant, hot liquid water is being transported in a pipe (k = 15 W/m .K, D₁ = 2.5 cm, Do=3 cm, and L = 10 m). The hot water flowing with a mass flow rate of 4.15Kg/s enters the pipe at 100°C and exits at 60°C. The plant supervisor thinks that since the hot water exits the pipe at 60°C, the pipe's outer surface temperature should be safe from thermal burn hazards. In order to prevent thermal burn upon accidental contact with skin tissue for individuals working in the vicinity of the pipe, the pipe's outer surface temperature should be kept below 45°C. Determine whether or not there is a risk of thermal burn on the pipe's outer surface. Assume the pipe outer surface temperature remains constant. The properties of water at the bulk mean temperature of Tb = (Ti+ Te)/2 = (100+60)/2 = 80°C are: Cp=4197 J/kg-K, k = 0.670 W/m-K, μ = 0.355 × 10-3 < 10-3 kg/m .s, and Pr = 2.22. The thermal conductivity of the pipe is given as Kpipe = 15 W/m .K.

In a food processing plant, hot liquid water is being transported in a pipe (k = 15 W/m .K, D₁ = 2.5 cm, Do=3 cm, and L = 10 m). The hot water flowing with a mass flow rate of 4.15Kg/s enters the pipe at 100°C and exits at 60°C. The plant supervisor thinks that since the hot water exits the pipe at 60°C, the pipe's outer surface temperature should be safe from thermal burn hazards. In order to prevent thermal burn upon accidental contact with skin tissue for individuals working in the vicinity of the pipe, the pipe's outer surface temperature should be kept below 45°C. Determine whether or not there is a risk of thermal burn on the pipe's outer surface. Assume the pipe outer surface temperature remains constant. The properties of water at the bulk mean temperature of Tb = (Ti+ Te)/2 = (100+60)/2 = 80°C are: Cp=4197 J/kg-K, k = 0.670 W/m-K, μ = 0.355 × 10-3 < 10-3 kg/m .s, and Pr = 2.22. The thermal conductivity of the pipe is given as Kpipe = 15 W/m .K.

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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