A 2-m-long, 4-cm-diameter electrical wire extends across a room at 20°C, as Shown in Fig. below. Heat is generated in the wire due to resistance heating, and the surface temperature of the wire is measured to be 252°C in steady operation. Also, the voltage drop and electric current through the wire are measured to be 80 V and 2 A, respectively. Heat loss transfer by radiation was 40 W from the surface of the 20 wire. Heat transfer coefficient for heat transfer between the outer surface of the wire and the air in the room. 2 A 80 V T 252 If the heat generation by electrical wire increased up to 200 W, what is the surface temperature of the wire, assuming no change in heat transfer coefficient?

A 2-m-long, 4-cm-diameter electrical wire extends across a room at 20°C, as Shown in Fig. below. Heat is generated in the wire due to resistance heating, and the surface temperature of the wire is measured to be 252°C in steady operation. Also, the voltage drop and electric current through the wire are measured to be 80 V and 2 A, respectively. Heat loss transfer by radiation was 40 W from the surface of the 20 wire. Heat transfer coefficient for heat transfer between the outer surface of the wire and the air in the room. 2 A 80 V T 252 If the heat generation by electrical wire increased up to 200 W, what is the surface temperature of the wire, assuming no change in heat transfer coefficient?

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.19P: 1.19 A cryogenic fluid is stored in a 0.3-m-diameter spherical container is still air. If the...

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