Question 3: An electronic device with a temperature of 84°C (shown in golden colour) isembedded inside a composite plastic tube which is equipped with three fins (shown in blue)to enhance the convective heat transfer with the surrounding air. The composite tube is heldhorizontally. The temperature drop along the fins can be ignored due to their high thermalconductivity. The outer ring of the fins (shown in brown) is insulated. The ambienttemperature is 20°C.3d. Calculate the heat transfer coefficients across the cylinder3e. Calculate the heat transfer coefficients across the fins by assuming fins as verticalplanes31. Calculate the heat loss across the systemAluminium finsDiameter = 30 cmInsulated ringThickness = 5 mmComposite tubeThickness = 5 mmThermal conductivity = 25 W/mkTube is held horizontally.Air20°CHot electronic deviceTemperature = 84°CDiameter = 10 cmLength = 100 cm%3D

It is asked to find the heat transfer coefficient over the horizontal tub as well as the vertical…

Answered: Question 3: An electronic device with a…

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 8.7P

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Similar questions

2.51 Determine by means of a flux plot the temperatures and heat flow per unit depth in the ribbed insulation shown in the accompanying sketch.
1.11 Calculate the heat loss through a glass window 7-mm thick if the inner surface temperature is 20°C and the outer surface temperature is 17°C. Comment on the possible effect of radiation on your answer.
1.1 On a cold winter day, the outer surface of a 0.2-m-thick concrete wall of a warehouse is exposed to temperature of –5°C, while the inner surface is kept at 20°C. The thermal conductivity of the concrete is 1.2 W/m K. Determine the heat loss through the wall, which is 10-m long and 3-m high. Problem 1.1
Determine the power requirement of a soldering iron in which the tip is maintained at 400C. The tip is a cylinder 3 mm in diameter and 10 mm long. The surrounding air temperature is 20C, and the average convection heat transfer coefficient over the tip is 20W/m2K. The tip is highly polished initially, giving it a very low emittance.
1.13 If the outer air temperature in Problem is –2°C, calculate the convection heat transfer coefficient between the outer surface of the window and the air, assuming radiation is negligible.
(a) If the cost of producing the hot water is $0.10 per kWh, what is the representative daily costof heat loss from an uninsulated pipe to the air per meter of pipe length? The convectionresistance associated with water flow in the pipe may be neglected.(b) Determine the savings associated with application of a 10-mm-thick coating of urethaneinsulation (k = 0.026 W/m-K) to the outer surface of the pipe.
A small, oxidized, horizontal metal tube with an OD of 0.0254 m (1 in.), 0.61 m (2 ft) long, and with a surface temperature at 588 K (600°F) is in a very large furnace enclosure with fire-brick walls and the surrounding air at 1088 K (1500°F). The emissivity of the metal tube is 0.60 at 1088 K and 0.46 at 588 K. Calculate the heat transfer to the tube by radiation using SI units and AES units.

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Principles of Heat Transfer (Activate Learning wi…

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ISBN:

9781305387102

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Kreith, Frank; Manglik, Raj M.

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