A radiator is a device used to dissipate heat. Some equipment generates a large amount of heat when working, and this excess heat cannot be dissipated quickly and accumulates to generate high temperatures, which may destroy the working equipment. At this point a radiator is needed. The radiator is a layer of good heat-conducting medium attached to the heating device, playing the role of a middleman. Sometimes fans and other things are added to the heat-conducting medium to speed up the heat dissipation effect. But sometimes the radiator also plays the role of a robber. For example, the radiator of a refrigerator forcibly removes heat to reach a temperature lower than room temperature.
The working principle of the radiator is that heat is transferred from the heating device to the radiator and then to air and other substances, where the heat is transferred through heat transfer in thermodynamics. The main methods of heat transfer include heat conduction, heat convection and heat radiation. For example, when a substance contacts a substance, as long as there is a temperature difference, heat transfer will occur until the temperature is the same everywhere. The radiator takes advantage of this, such as using good thermal conductive materials, and the thin and large fin-like structure increases the contact area and heat conduction speed between the heating device and the radiator to air and other substances.
The central processing unit, graphics card, etc. in the computer will emit waste heat when running. The radiator can help dissipate the waste heat that the computer continues to emit, so as to prevent the computer from overheating and damaging the electronic parts inside. Radiators used for computer cooling usually use fans or water cooling. [1] In addition, some overclocking enthusiasts use liquid nitrogen to help computers dissipate a large amount of waste heat, allowing the processor to operate at a higher frequency.
The basic function of the refrigerator is to cool down to preserve food, so it must drain away the room temperature inside the box and maintain an appropriate low temperature. The refrigeration system generally consists of four basic components: compressor, condenser, capillary tube or thermal expansion valve, and evaporator. Refrigerant is a liquid that can boil at low temperature under low pressure. It absorbs heat when boiling. The refrigerant circulates continuously in the refrigeration system. The compressor increases the gas pressure of the refrigerant, causing liquefaction conditions. When it passes through the condenser, it condenses and liquefies and releases heat. , and then reduce the pressure and temperature when passing through the capillary tube, and then boil and vaporize to absorb heat when passing through the evaporator. In addition, refrigeration diodes are now being used, without complicated mechanical devices, but with poor performance, and are used in small refrigerators.
Air cooling, heat dissipation is the most common, and it is very simple, it is to use a fan to take away the heat absorbed by the radiator. The price is relatively low and the installation is simple, but it is highly dependent on the environment. For example, the heat dissipation performance will be greatly affected when the temperature rises.
A heat pipe is a heat transfer element with extremely high thermal conductivity. It transfers heat through the evaporation and condensation of liquid in a fully enclosed vacuum tube. It uses fluid principles such as capillary suction to achieve a cooling effect similar to that of a refrigerator compressor. . It has a series of advantages such as high thermal conductivity, excellent isothermal properties, heat flow density variability, reversibility of heat flow direction, long-distance heat transfer, constant temperature characteristics (controllable heat pipe), thermal diode and thermal switch performance, and is composed of The heat exchanger composed of heat pipes has the advantages of high heat transfer efficiency, compact structure, and low fluid resistance loss. Due to its special heat transfer characteristics, the tube wall temperature can be controlled to avoid dew point corrosion. But the price is relatively high.
Liquid cooling uses liquid to be forced to circulate under the driving of a pump to take away the heat from the radiator. Compared with air cooling, it has the advantages of being quiet, stable cooling, and less dependent on the environment. However, the price of liquid cooling is relatively high, and installation is relatively troublesome.
Semiconductor refrigeration uses a piece of N-type semiconductor material and a piece of P-type semiconductor material to form a galvanic pair. When a DC current is connected in this circuit, energy transfer can occur. The current flows from the N-type element to the joint of the P-type element and is absorbed. The heat becomes the cold end and flows from the P-type component to the joint of the N-type component. The heat is released and becomes the hot end, thereby producing thermal conductivity. [2]
Compressor refrigeration sucks in low-temperature and low-pressure refrigerant gas from the suction pipe, compresses it through the compressor, and discharges high-temperature and high-pressure refrigerant gas to the exhaust pipe to provide power for the refrigeration cycle, thus achieving compression → condensation → expansion → Evaporation (heat absorption) refrigeration cycle. Such as air conditioners and refrigerators.