Types of Heat Transfer
Heat transfer is the process of heat transfer (energy exchange).
Everything here is quite simple, there are only three types: thermal conductivity, convection and radiation.
Thermal conductivity
That type of heat transfer that can be characterized as the ability of bodies to conduct energy from a more heated body to a less heated one.
It's about transferring heat through contact. Admit it, have you ever warmed yourself near a radiator? If you sat close to it, then you warmed up due to thermal conductivity. Cuddling a cat who has a hot belly is also effective.
Sometimes we go a little overboard with the possibilities of this effect when we lie down on the hot sand at the beach. There is an effect, but not a very pleasant one. Well, an ice heating pad on your forehead has the opposite effect - your forehead transfers heat to the heating pad.
Convection
When we talked about thermal conductivity, we used a battery as an example. Conduction is when we get heat by touching a battery. But all the things in the room do not touch the radiator, and the room is heated. This is where convection comes in .
The fact is that cold air is heavier than hot air (cold air is simply denser). When the battery heats a certain volume of air, it immediately rises to the top, passes along the ceiling, has time to cool down and go back down to the battery, where it heats up again. Thus, the entire room is heated evenly, because increasingly hot currents replace increasingly colder ones.
Radiation
We already mentioned the beach, but we were talking only about the hot sand. But the heat from the sun is radiation . In this case, heat is transferred through waves.
If we warm ourselves by the fireplace, do we receive heat by convection or radiation?
