9 A wire of radius r1 = 0.7cm and thermalconductivity k= 8 w/m.Co. Electrical energy isconverted to heat energy by wire at constantrate per unit volume e'= 3.3x10® W/m³ andheat is transferred to water at 109°C byconvection heat transfer coefficient h = 2128W/m?.C°Assuming study one dimension heat transferfind temperature at center.

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A wire of radius r1 = 0.7cm and thermal conductivity k= 8 w/m.C°. Electrical energy is converted to heat energy by wire at constant rate per unit volume e'= 3.3×10® W/m³ and heat is transferred to water at 109°C by convection heat transfer coefficient h = 2128 W/m?.C° Assuming study one dimension heat transfer find temperature at center.

A wire of radius r1 = 0.7cm and thermal conductivity k= 8 w/m.C°. Electrical energy is converted to heat energy by wire at constant rate per unit volume e'= 3.3×10® W/m³ and heat is transferred to water at 109°C by convection heat transfer coefficient h = 2128 W/m?.C° Assuming study one dimension heat transfer find temperature at center.

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.

Chapter3: Transient Heat Conduction

Section: Chapter Questions

Problem 3.17P: 3.17 A 1.4-kg aluminum household iron has a 500-W heating element. The surface area is . The ambient...

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3.17 A 1.4-kg aluminum household iron has a 500-W heating element. The surface area is . The ambient temperature is 21°C, and the surface heat transfer coefficient is . How long after the iron is plugged in does its temperature reach 104°C?
2.2 A small dam, which is idealized by a large slab 1.2 m thick, is to be completely poured in a short Period of time. The hydration of the concrete results in the equivalent of a distributed source of constant strength of 100 W/m3. If both dam surfaces are at 16°C, determine the maximum temperature to which the concrete will be subjected, assuming steady-state conditions. The thermal conductivity of the wet concrete can be taken as 0.84 W/m K.
An electric motor is to be connected by a horizontal steel shaft (k - 42.56 W/m.K), 25 mm in diameter to an impeller of a pump, circulating liquid metal at a temperature of 540°C. If the temperature of electric motor is limited to a maximum value of 52°C with the ambient air at 27°C and heat transfer coefficient of 40.7 W/m?K, what length of shaft should be specified between the motor and pump ?
A 10-mm-inner-diameter pipe made of commercial steel is used to heat a liquid in an industrial process. The liquid enters the pipe with Ti=25°C, V=0.8 m/s. A uniform heat flux is maintained by an electric resistance heater wrapped arounf the outer surface of the pipe, so that the fluid exits at 75°C. Assuming fully developed flow and taking the average fluid properties to be ρ=1000 kg/m3, cp=4000 J/kg·K, µ=2x10-3 kg/m·s, k=0.48 W/m·K, and Pr=10, determine: The required surface heat flux , produced by the heater The surface temperature at the exit, Ts The pressure loss through the piper and the minimum power required to overcome the resistance to flow.
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