13 - Radiation Heat Transfer Flashcards

1
Q

Assumptions for radiation heat transfer

A

Uniform
Isothermal
Diffuse
Medium has no impact

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define view factor

A

Purely geometric quantity and is independent of the surface properties and temperature
(also called ‘shape factor’, ‘configuration factor’ and ‘angle factor’)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define diffuse view factor

A

View factor based on the assumption that the surfaces are diffuse emitters and diffuse reflectors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Define specular view factor

A

View factor based on the assumption that the surfaces are diffuse emitters but specular reflectors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Summation rule

A

Sum of the view factors from a surface i of an enclosure to all surfaces of the enclosure, including to itself, must equal unity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Superposition rule

A

The view factor from a surface i to a surface j is equal to the sum of the view factors from surface i to the parts of surface j

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Symmetry rule

A

Two (or more) surfaces that possess symmetry about a third surface will have identical view factors from that surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Define radiosity

A

Total radiation energy leaving a surface per unit time and per unit area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

When are some surfaces modelled as being adiabatic?

A

If their back sides are well insulated and net heat transfer through them is zero

How well did you know this?
1
Not at all
2
3
4
5
Perfectly