Radiator: cooling mode

Heat dissipation mode refers to the main mode of heat dissipation of the radiator. In thermodynamics, heat dissipation is heat transfer, and there are three main ways of heat transfer: heat conduction, heat convection and heat radiation. When material itself or material contacts with material, the transmission of energy is called heat conduction, which is the most common way of heat transfer. For example, the direct contact between the CPU heatsink base and the CPU to take away heat belongs to heat conduction. Thermal convection refers to the heat transfer mode in which the flowing fluid (gas or liquid) passes through the tropical zone. The "forced thermal convection" cooling mode in which the cooling fan drives the gas flow is more common in the cooling system of the computer case. Thermal radiation refers to the transfer of heat by radiation, and the most common daily is solar radiation. These three heat dissipation modes are not isolated. In daily heat transfer, these three heat dissipation modes all occur at the same time and work together.

In fact, any type of radiator will basically use the above three heat transfer modes at the same time, but with different emphasis. For example, ordinary CPU air cooling radiator, the CPU heat sink is in direct contact with the CPU surface, and the heat on the CPU surface is transferred to the CPU heat sink through heat conduction; The air flow generated by the cooling fan takes away the heat on the surface of the CPU heat sink through thermal convection; The air flow in the chassis also takes away the heat of the air around the CPU heat sink through thermal convection until it is outside the chassis; At the same time, all parts with high temperature will generate thermal radiation to parts with low ambient temperature.

The heat dissipation efficiency of the radiator is related to the heat conductivity of the radiator material, the heat capacity of the radiator material and the radiating medium, and the effective heat dissipation area of the radiator.

According to the way of taking heat away from the radiator, the radiator can be divided into active heat dissipation and passive heat dissipation. The former is commonly air-cooled radiator, while the latter is commonly radiator fins. Further subdivision of heat dissipation modes can be divided into air cooling, heat pipe, liquid cooling, semiconductor refrigeration, compressor refrigeration, etc.

    Air-cooled Heat dissipation is the most common and very simple, which is to use a fan to take away the heat absorbed by the radiator. It has the advantages of relatively low price and simple installation, but it is highly dependent on the environment. For example, its heat dissipation performance will be greatly affected when the temperature rises and overclocking occurs.

    heat pipe It is a heat transfer element with extremely high thermal conductivity. It transfers heat through the evaporation and condensation of liquid in a totally enclosed vacuum tube. It uses the fluid principle such as gross absorption to have a refrigeration effect similar to that of a refrigerator compressor. It has a series of advantages such as extremely high thermal conductivity, good isothermal property, the heat transfer area of both cold and hot sides can be arbitrarily changed, long-distance heat transfer can be achieved, and temperature can be controlled. Moreover, the heat exchanger composed of heat pipes has the advantages of high heat transfer efficiency, compact structure, small fluid resistance loss, etc. Due to its special heat transfer characteristics, it can control the pipe wall temperature and avoid dew point corrosion.

    Liquid cooling It uses the liquid driven by the pump to carry away the heat of the radiator by forced circulation, which has the advantages of quiet, stable temperature drop, less dependence on the environment and so on compared with air cooling. However, the price of heat pipe and liquid cooling is relatively high, and the installation is relatively troublesome.

When choosing radiators, you can choose them according to your actual needs and economic conditions. The principle is that enough is enough.