Methods Of Heat Flow
There are three different means by which heat flows. All three play a role in the mechanical refrigeration, and work together to make the heat transfer happen. Heat transfer : conduction, convection and radiation. We'll have more details on each of these indication of the period, and then by examining each method, as it happens in three parameters: first, in nature; secondly, as it appears in the space the load; and finally, as it applies to equipment as capacity-building. In nature, we see no forms are clearly separated. They are usually mixed together. Conduction is the transfer of heat from molecule to molecule through a substance, on a chain collision. Heat added in one place causes the temperature of the substance when heated to go up because the molecules move faster. These high velocities of the molecules start a chain collision with molecules nearthem. Chain reaction is moved throughout the material. When the conduct occurs in gases and liquids, it works better when the molecules are densely Packed, as they in solids.
If one end of an iron bar is kept in the flame, carrying out in the end will cause it to become too hot to hold.
Through roofs, walls, doors and Windows that allows heat to enter tightly sealed house, as the load on the cooling system. The holding is also what allows the cooling coil to ensure the capacity to cool the air. The heat from the air moves in the cold refrigerant by carried through the tubes and fins the cooling coil. Convective heat transfer during movement or flow of molecules from one place to another. Heated molecules within the current environment, such as air transport their heat directly in the area. In forced air heating system, for example, the air flowing through the conditioned space carries heat by convection.
Convective flows easily see in a pot of water, heated on a stove, especially just before boiling begins. Natural convection, currents, as they are also called "current density", because their movement is caused by differences in density of the liquid, due to temperature difference. Less dense fluids tend to increase, while the more dense fluids fall. In cold climates, convection causes heavy, cold air form a downdraft " outside the walls and especially windows. As a new air rushes for what falls from windows, heat is transferred from the top of the windows, where she is a loss of heat (thermal loading) for space. In this case, convection causes discomfort of cold "puddle" the air that accumulates on the floor.
Convection may also be at work, as heat capacity, when baseboard heater is installed below a cool box. As less dense hot air moves upward, he takes the heat load power at the window, wall and ceiling. As air molecules lose heat energy, they become colder and denser, falls to the floor. Cool air moves in a heater to compensate for the warm air moves upward; this fixes and downdraft cold puddle problem.
Radiation is the most common and least understood, the method of heat transfer. This is the most common because most of the thermal energy of our planet comes from solar radiation. He would have realized because of the radiant heat cannot be defined in terms of facing and moving molecules. Radiant heat is usually behaves like a wave form of energy, but also possesses some of the qualities, energetic, moving particles. Radiant heat has the ability to go from one place to another without heating in the zone between them. For example, a tourist, sitting in front of a fire on a cold night can keep warm, while the air between him and the fire remains cold. This is because of the radiant heat can only heat that it hits. As a consequence, camper front side heats up, but his back is cold.
Radiant heat can only heat materials in which it is absorbed. Camper will receive a warm wearing dull, black clothing, and will remain cold, wearing reflective clothing other things being equal. That is why people in a hot, Sunny climate, as a rule, dressed in white robes. White is a good reflector of the sun radiant heat energy.
Solar radiation comes through the Windows in the building, strikes walls, floors, furniture and people, and is absorbed by them. As it is absorbed, it heats up the space and becomes a cooling load, which may need to be removed by cooling equipment. Radiant heat is sometimes used for heating power from overhead as a way of warming people or products without heating the air between them, or the entire area. Radiant heat is almost always seen in conjunction with other forms of heat...
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Refrigeration 
