A heat pipe radiator is a type of heat conduction device that achieves heat dissipation through the principle of heat pipes. A heat pipe radiator consists of a heat pipe, heat dissipation fins, and a heat dissipation base.
Heat pipe is the core component of a heat pipe radiator, which is a hollow pipe filled with a certain amount of working medium. Commonly used working media include pure water, ammonia, methanol, etc. The inner wall of the heat pipe is coated with a high-temperature evaporation surface, and materials such as polytetrafluoroethylene are usually used to enhance the high-temperature resistance of the heat pipe.
The working principle of heat pipes is based on the vaporization and condensation processes of liquids. When one end of the heat pipe is heated by a heat source, the high temperature on the heat source causes the working medium liquid to evaporate into steam in the high-temperature area of the inner wall of the heat pipe. The pressure gradient of steam causes it to transfer to the colder end and condense into a liquid in the low-temperature region of that end. The condensed liquid forms a liquid plug due to the surface tension of the liquid, and uniformly flows back towards the heat source end on the inner wall of the heat pipe through capillary force, forming a cycle.
The heat transfer performance of heat pipes is mainly affected by the following factors:
1. Selection of working medium: Different working media have different evaporation and condensation temperatures, and selecting the appropriate working medium is the key to achieving efficient heat transfer.
2. Inner diameter and wall thickness of heat pipes: The inner diameter and wall thickness of heat pipes determine their heat transfer and pressure resistance capabilities. The larger the inner diameter, the stronger the heat transfer ability; The thinner the wall thickness, the higher the heat transfer ability, but the corresponding decrease in pressure resistance.
3. Length and curvature of heat pipes: The length and curvature of heat pipes can affect their heat transfer efficiency and flow resistance. Shorter heat pipes can achieve higher heat transfer efficiency, but also increase flow resistance; A smaller curvature can reduce flow resistance and improve heat transfer efficiency.
4. Contact method between heat pipe and heat dissipation carrier: Heat pipe is generally welded or glued to the heat dissipation carrier, and the quality of contact method will affect the size of thermal resistance, thereby affecting the heat dissipation effect.
Heat dissipation fins are another important component of heat pipe radiators, whose function is to increase the heat dissipation area and improve the heat dissipation efficiency. Heat dissipation fins are usually made of aluminum alloy or copper material, and their surfaces are usually CNC drilled to provide a larger surface area. During installation, the heat dissipation fins come into contact with the heat source, guiding heat to the heat pipe through heat conduction between them.
The heat dissipation base is a component that fixes the heat pipe and heat dissipation fins together, usually made of aluminum alloy and has good heat dissipation performance. The important role of the heat dissipation base is to evenly transfer heat to the heat pipe and fins, ensuring the working effect of the entire heat dissipation system.
The working process of a heat pipe radiator can be summarized as follows:
1. The heat source generates heat, causing one end of the heat pipe to be heated.
2. The working medium in the high-temperature area of the inner wall of the heat pipe evaporates into steam, which is transmitted to the cooler end.
3. Steam condenses into liquid in the low-temperature area at the colder end, forming a liquid plug and returning to the heat source end.
4. The heat dissipation fins transfer heat from the heat source to the heat pipe.
5. The heat pipe transfers heat to the heat dissipation base and ultimately dissipates it into the surrounding environment through the heat dissipation surface of the heat dissipation base and fins.
In summary, a heat pipe radiator achieves heat transfer and dissipation through the evaporation and condensation process of the heat pipe. The interior of its heat pipe is filled with working medium. In the high-temperature area of the heating end, the working medium evaporates into steam, and then condenses into liquid in the low-temperature area of the cooling end, forming a closed cycle. The heat pipe is combined with the heat dissipation fins and base to transfer heat from the heat source to the heat dissipation fins, and ultimately to the surrounding environment through the heat dissipation fins and base, achieving the effect of heat dissipation. This heat dissipation method has the characteristics of high efficiency, balance, and reliability, and has been widely used in high-power electronic devices, optoelectronic devices, and other fields.
