Heat is transmitted in three ways: conduction - by transport or load - by radiation.
CONNECTION:
This is what happens when a hot substance is found with a colder material, where the heat is naturally transferred from the warmer material. If you put your hand in a bowl with cold water, your hand will become colder, and the water will then become warmer.
Thermal transfer:
The heat of the air around a hot material is increased by thermal transfer. The hot air is less dense than the cold air, so it rises to replace the cold air at the top (see why the blown balloon rises with hot air?) And the process continues until the heat of this object or substance coolens and becomes equivalent to the atmosphere of the room.
(The central heating system works with the thermal transfer system, and unless it is dyed in non-glossy black, it would be more logical to call it "thermal heating devices").
Thermal radiation:
Although all the heat produced by the coal heater or conventional wood exits out through the chimney through thermal transfer, the warmth of the room is transmitted by thermal radiation. (This type of radiation does not require a conveyor medium, which means that things, for example, in a vacuum cleaner will cool down, so they can transfer the surrounding heat to other objects, even though there is no possibility of heating through convection or heat. The sun was able to heat the earth).
Bright surfaces and light colors are low-radiation materials that absorb heat compared to dark and dark colors. the examples for the truth of these words are so much in our daily lives. We note that the hood of the cooling water tank in the engine of the car always looks black and unsaturated so as to encourage the loss of some water temperature by radiation.
It should be noted here that this applies to all forms of radiation - not just heat. For example, the outer surfaces of some warplanes are painted in glossy black until the radar waves are absorbed by the radar and the plane becomes invisible and can not be traced.
The same principle applies to how aluminum can keep food warm, or make it possible to use it to heat or cook food quickly. If you put the glossy side of the aluminum foil inside, you will be able to keep the food warm, or you will reduce the cooking time.
Another example of the same phenomenon is the space blanket, used by rescue teams in cold climates, where this blanket is made of wind and water resistant materials covered by a layer of reflective aluminum or aluminum. If the rescuer wraps the glossy part around the victim, he will be able to maintain as much heat as possible on the latter's body.
Similarly, if you look inside the vacuum cleaner you will see that the interior surfaces are silver. And the broom prevents the transfer of heat and dust from them through the conduction or transport, but the inner surface of the internal reduces any transmission through radiation .. And cold materials ?!
The advantages of aluminum foil are not limited to maintaining the hottest things. but, it exceed to the righteous material too.
If you wrap a sandwiches with aluminum foil on the outside, this kind of paper will keep you cool, unlike the heat outside the sandwiches, which keeps them fresh, rather than being exposed to air.
CONNECTION:
This is what happens when a hot substance is found with a colder material, where the heat is naturally transferred from the warmer material. If you put your hand in a bowl with cold water, your hand will become colder, and the water will then become warmer.
Thermal transfer:
The heat of the air around a hot material is increased by thermal transfer. The hot air is less dense than the cold air, so it rises to replace the cold air at the top (see why the blown balloon rises with hot air?) And the process continues until the heat of this object or substance coolens and becomes equivalent to the atmosphere of the room.
(The central heating system works with the thermal transfer system, and unless it is dyed in non-glossy black, it would be more logical to call it "thermal heating devices").
Thermal radiation:
Although all the heat produced by the coal heater or conventional wood exits out through the chimney through thermal transfer, the warmth of the room is transmitted by thermal radiation. (This type of radiation does not require a conveyor medium, which means that things, for example, in a vacuum cleaner will cool down, so they can transfer the surrounding heat to other objects, even though there is no possibility of heating through convection or heat. The sun was able to heat the earth).
Bright surfaces and light colors are low-radiation materials that absorb heat compared to dark and dark colors. the examples for the truth of these words are so much in our daily lives. We note that the hood of the cooling water tank in the engine of the car always looks black and unsaturated so as to encourage the loss of some water temperature by radiation.
It should be noted here that this applies to all forms of radiation - not just heat. For example, the outer surfaces of some warplanes are painted in glossy black until the radar waves are absorbed by the radar and the plane becomes invisible and can not be traced.
The same principle applies to how aluminum can keep food warm, or make it possible to use it to heat or cook food quickly. If you put the glossy side of the aluminum foil inside, you will be able to keep the food warm, or you will reduce the cooking time.
Another example of the same phenomenon is the space blanket, used by rescue teams in cold climates, where this blanket is made of wind and water resistant materials covered by a layer of reflective aluminum or aluminum. If the rescuer wraps the glossy part around the victim, he will be able to maintain as much heat as possible on the latter's body.
Similarly, if you look inside the vacuum cleaner you will see that the interior surfaces are silver. And the broom prevents the transfer of heat and dust from them through the conduction or transport, but the inner surface of the internal reduces any transmission through radiation .. And cold materials ?!
The advantages of aluminum foil are not limited to maintaining the hottest things. but, it exceed to the righteous material too.
If you wrap a sandwiches with aluminum foil on the outside, this kind of paper will keep you cool, unlike the heat outside the sandwiches, which keeps them fresh, rather than being exposed to air.
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