A row of long cylindrical power cables that are spaced 2 cm evenly apart is placed in parallel with a plate (k = 15 W/m-K). The plate has a thickness of 5 cm, and its lower and upper surface temperatures are To=227°C and T₁ = 207°C, respectively. The power cables are shielded with polyethylene insulation, and the diameter of each cable is 1 cm. The opposite wall is at a temperature of T3 = 20°C. The upper surface of the plate experiences convection with air at 20°C and a convection heat transfer coefficient of 20 W/m2.K. According to the ASTM D1351-14 standard specification, the polyethylene insulation is suitable for operation at temperatures up to 75°C. Determine the surface temperature of the cable and check whether the polyethylene insulation for the power cables would comply with the ASTM D1351-14 standard specification. All surfaces can be approximated as blackbodies. D To- Air, h, Too Plate, k Wall -Power cable The surface temperature of the cables is 127 °C. Yes , the polyethylene insulation for the power cables will comply with the ASTM D1351-14 standard specification.

A row of long cylindrical power cables that are spaced 2 cm evenly apart is placed in parallel with a plate (k = 15 W/m-K). The plate has a thickness of 5 cm, and its lower and upper surface temperatures are To=227°C and T₁ = 207°C, respectively. The power cables are shielded with polyethylene insulation, and the diameter of each cable is 1 cm. The opposite wall is at a temperature of T3 = 20°C. The upper surface of the plate experiences convection with air at 20°C and a convection heat transfer coefficient of 20 W/m2.K. According to the ASTM D1351-14 standard specification, the polyethylene insulation is suitable for operation at temperatures up to 75°C. Determine the surface temperature of the cable and check whether the polyethylene insulation for the power cables would comply with the ASTM D1351-14 standard specification. All surfaces can be approximated as blackbodies. D To- Air, h, Too Plate, k Wall -Power cable The surface temperature of the cables is 127 °C. Yes , the polyethylene insulation for the power cables will comply with the ASTM D1351-14 standard specification.

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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