A cylindrical resistance heater is placed horizontally in air. The outer surface temperature of the resistance wire is to be determined. The environment temperature Tair = 40.0°C and the power of the resistance heater is 310.0W, The length and the diameter of the resistance heater is 0.75 m and 0.5 cm. Resistance Air heater, T, T. D=0.5 cm L = 0.75 m The properties of air at 1atm and 500°C are: k = 0.05572W - mª - K¯' v = 7.804 x 10 5m² ·s! Pr = 0.6986 в - 0.001204K- Hint: Start your guess from 1150.0°C. Nu = | 0.6 + 0.387RA 1+ 0599 Pr Iterate at least for 2 times.

A cylindrical resistance heater is placed horizontally in air. The outer surface temperature of the resistance wire is to be determined. The environment temperature Tair = 40.0°C and the power of the resistance heater is 310.0W, The length and the diameter of the resistance heater is 0.75 m and 0.5 cm. Resistance Air heater, T, T. D=0.5 cm L = 0.75 m The properties of air at 1atm and 500°C are: k = 0.05572W - mª - K¯' v = 7.804 x 10 5m² ·s! Pr = 0.6986 в - 0.001204K- Hint: Start your guess from 1150.0°C. Nu = | 0.6 + 0.387RA 1+ 0599 Pr Iterate at least for 2 times.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

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Publisher:Kreith, Frank; Manglik, Raj M.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.4P: An electrical transmission line of 1.2-cm diameter carries a current of 200 amps and has a...

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Concept explainers

Conduction and Convection

When energy travels from one object to another it is said to have undergone heat transfer. Heat transfer is nothing but the transfer of thermal energy or internal energy from one thing to another, like e.g., when a vessel with water, kept on top of a burner, heats up because of the flame underneath it.

Question

100%

A cylindrical resistance heater is placed horizontally in air. The outer surface temperature of the resistance wire is to be determined.

The environment temperature

and the power of the resistance heater is .

The length and the diameter of the resistance heater is 0.75 m and 0.5 cm.

A cylindrical resistance heater is placed horizontally in air. The outer surface temperature of the
resistance wire is to be determined.
The environment temperature
Tair = 40.0°C
and the power of the resistance heater is 310.0W.
The length and the diameter of the resistance heater is 0.75 m and 0.5 cm.
Resistance
heater, T,
Air
T.
|D=0.5 cm
L= 0.75 m
The properties of air at 1atm and 500°C are:
k = 0.05572W · m
-1
K
v = 7.804 x 10m? - s1
Pr = 0.6986
-1
B= 0.001294K
Hint:
Start your guess from 1150.0°C.
0.387RA
Nu
0.6 +
1+
0599
/Pr
Iterate at least for 2 times.

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