Explain convection heat transfer using kinetic theory

In summary, the conversation discusses the concept of convection heat transfer and mass transfer, specifically in relation to a hot wall in contact with a gas. The use of kinetic theory of gases and collisions between molecules is mentioned. While explanations for other phenomena such as viscosity and heat exchange without gravity are available, an explanation for convection has not been found. The suggestion is made to think about the forces at play and the interaction between the hot fluid and surrounding fluid to understand the development of a convection effect.
  • #1
kevinaltieri
4
0
I am trying to explain the convection heat transfer and the mass transfer related (buoyancy of the heated part of the gas) using only kinetic theory of gases , I mean using only collisions between molecules of the gas. The environment is the usual one : a hot wall in contact with a gas. Normally this problem is treated using a simple model of gas heated by the wall and expanded that is pushed up against gravity.
I have found explanation of viscosity, heat exchange without gravity, diffusion using kinetic theory. I have not found explanation of convection. Could somebody give some informations. Thanks
 
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  • #2
I'll try to give you some hints, to help you find the answer and not give you a whole answer, because I think this is the right way of learning anything.
When whatever fluid you have, is in contact with a hotter object - a hot wall for that matter, fluid gets energy via conduction, so its density decreases. Now, you have to think about the upward and downward forces, using a very simple line of thinking and see what happens with the volume of hot fluid. When you arrive there, there is an interaction with surrounding fluid that develops a convection effect, in order to account for the pressure difference.
 

1. What is convection heat transfer?

Convection heat transfer is the transfer of heat through a fluid or gas due to the movement of the particles within the fluid.

2. How does kinetic theory explain convection heat transfer?

Kinetic theory states that all particles in a substance are in constant motion. In the case of convection heat transfer, the particles in the fluid or gas are heated, causing them to move faster and spread out. This creates areas of higher and lower density, which results in the transfer of heat energy from hot regions to cooler regions.

3. What factors affect convection heat transfer?

The rate of convection heat transfer is influenced by the temperature difference between the hot and cold regions, the properties of the fluid or gas (such as density and viscosity), and the surface area and shape of the objects involved.

4. How is convection heat transfer different from conduction heat transfer?

Conduction heat transfer occurs within a solid material, where heat is transferred through direct contact between particles. In convection heat transfer, the particles in a fluid or gas are moving and transferring heat energy between each other, resulting in the transfer of heat between two objects.

5. What are some real-world examples of convection heat transfer?

Examples of convection heat transfer include the heating of a room through a radiator, the boiling of water in a pot, and the circulation of warm and cool air in the atmosphere.

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