Question

In: Mechanical Engineering

The inner and outer surface temperatures of a glass window 5 mm thick are 15 and...

The inner and outer surface temperatures of a glass window 5 mm thick are 15 and 5°C. The thermal resist- ance of the glass window due to conduction is Rt,cond = 1.19 × 10−3 K/W. What is the rate of heat loss through a 1 m × 3 m window? What is the thermal conductivity of the glass?

Expert Solution

Assumption: 1. One dimensional heat flow i.e heat is flowing only in a direction perpendicular to the cross sectional area.

2. Temperatures on both surfaces of the walls are uniform.

The heat loss due to conduction through a wall is given by Fourier's law of heat conduction.

It is given as,

Where,

K = thermal conductivity

A = Area of cross section through which heat is being conducted.

= Temperature difference between two surfaces

L = Thickness of the wall

Using electrical analogy, we can rewrite Fourier's law as follows,

R_th = Thermal resistance analogous to electrical resistance and analogous to potential difference.

It is given that,

Finding heat loss,

samet mamat answered 2 years ago

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