Usually these cables are very thick and surrounded by protective material but you work for a company whose R&D is focused on developing a new material for submarine cables that allows them to be both electrically conductive and durable enough to withstand the harsh conditions of the ocean. Assume the cable being analyzed is made up of one core material with uniform properties throughout. These cables have a radius of only 0.5mm and some unknown but very long length L (keep your analysis in terms of this unknown length - don't assume a value for it in your written work). The water through which this cable runs is flowing very fast and has a convection coefficient of 450W/m² K and temperature of 25°C. You can assume that this water is touching the entire length of the cable you are analyzing on its entire surface. The special cable material has a density of 7500kg/m³, specific heat capacity of 500J/kgK, and a thermal conductivity of 20W/mK. Electric current flows through the cable at 220A, and its electrical resistance per unit length is 0.019/m.

Usually these cables are very thick and surrounded by protective material but you work for a company whose R&D is focused on developing a new material for submarine cables that allows them to be both electrically conductive and durable enough to withstand the harsh conditions of the ocean. Assume the cable being analyzed is made up of one core material with uniform properties throughout. These cables have a radius of only 0.5mm and some unknown but very long length L (keep your analysis in terms of this unknown length - don't assume a value for it in your written work). The water through which this cable runs is flowing very fast and has a convection coefficient of 450W/m² K and temperature of 25°C. You can assume that this water is touching the entire length of the cable you are analyzing on its entire surface. The special cable material has a density of 7500kg/m³, specific heat capacity of 500J/kgK, and a thermal conductivity of 20W/mK. Electric current flows through the cable at 220A, and its electrical resistance per unit length is 0.019/m.

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.36P

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