Question

Heat transfer ( related nuclear engineering a little bit )

I got some Short-answer questions (2~3 sentences)

I want to know that

1) Definition of convective heat transfer coefficient

2) Frequency range of radiation heat transfer

3) Constant temperature condition VS constant heat flux

4) Coupling of equations in natural convection

5) Core acceleration

Answer 1

Answers

1) Convective heat transfer coefficient : The amount of heat transmitted for a unit temperature difference between the fluid and unit area of surface in unit time.

  

2) thermal radiation wavelength range: 10^-7 to 10^-4 m

Frequency range,

c = 3 X 10⁸ m/s

so frequency range, 3 X 10¹² to 3 X 10¹⁵ Hz

3) Suppose a hot fluid is flowing through a pipe, there are two conditions :

i) if the outer surface of the pipe remains at constant temperature than it is constant temperature condition

ii) if the heat flux going out from the surface of pipe is constant than it is constant heat flux condition