Views: 57 Author: Site Editor Publish Time: 2022-01-21 Origin: Site
Are you looking for a more efficient way to cool your electronic components?
If so, you may want to consider using a heat pipe heat sink. Heat pipe technology has been around for decades, and it's still one of the most effective ways to dissipate heat.
This article will discuss what a heat pipe is and how it works. Additionally, we'll discuss some of the benefits of using heat pipes as heat sinks. Read on to find out more!
Heat pipe heat sinks are made from a sealed metal tube filled with a liquid.
The heat-generating part of the device (the semiconductor, for example) sits in the middle of one end and produces heat.
The heat is passed to the liquid in the pipe, which travels to the other end of the tube.
A fan at this end of the pipe provides airflow across it, forcing the liquid's heat into the surrounding atmosphere.
A heat pipe is a heat transferring device. A sealed metal tube containing liquid is encased in insulation with one end exposed to the atmosphere and the other submerged in a fluid so its interior can vaporize without boiling away.
This vapour condenses again on the tube walls close to where it enters as it travels through the tube.
The process cools by extracting sensible heat from higher temperature regions near one end of the pipe to areas near the other end at a lower temperature.
By removing latent energy as slugs of liquid moving around inside have tugged on their surrounding gases molecules tugging rather than just being reprocessed.
So you can say that if materials are hot, they radiate energy out, which might be felt as hot.
In a closed tube capillary, the liquid would boil away and fail.
Still, by adding an opening to allow some of it to return to its calm rest position in contact with the metal, it has time to remove the latent energy from gas molecules tugging on them before they can return to their normal state where they no longer pull on other molecules.
Heat pipes keep a moving liquid cool by allowing it to evaporate into a gas and condense back into a liquid on the other end, where there is already a lower temperature.
Heat pipes are simply metal lengths containing a liquid that heats up to evaporate into gas, then condenses back to liquid at the other end. The cool thing about them is they use this process of evaporation and condensation to transfer heat.
The technical characteristics of a heat pipe include the following:
The heat pipe has a closed inner tube containing working fluid sealed at the ends, with each end exposed to different conditions. The first end (condenser) is normally open to the outside air or atmosphere, while the other (evaporator) vaporizes the liquid. It may also be plugged by external means, such as a plug of porous material, which prevents liquid from leaving the tube.
The length and diameter of the heat pipe greatly affect its performance (the product's it very much and involve many design trade-offs). Normally, the working fluid moves along the length of the tube by natural circulation caused by vaporization at the hot end and condensation at the cold end. The heat pipe is used to move heat in one direction only (unidirectional).
The working fluid may be almost any liquid or vapour, but must have suitable vapor pressure and viscosity. These two properties determine the height of the condensed liquid above the evaporator, which along with the volume flow rate of gas, determines how much heat can be transferred within a given time.
The working fluid must have suitable thermal properties, such as high specific heat capacity and latent heat of vaporization (to slow down the rate at which it turns from liquid to vapour). To minimize freezing the fluid should also have a low freezing point.
This makes the tube easy to drain off liquid (de-freeze) if the heat pipe is exposed to temperatures below its operating temperature.
The most common working fluid is water, but it can also be ammonia, ethanol, or methanol. Heat pipes with large diameters are used for building and industrial process heating since they carry larger amounts of heat per unit length than smaller diameter units.
The heat dissipation principle of a heat pipe is simple:
The hot end is connected to a component that emits waste heat, while the cold end of the pipe is cooled by contact with air or a liquid.
The working fluid in the pipe absorbs this waste heat and carries it away, vaporizing as it does so.
The vaporization process creates a pressure differential between the two ends of the pipe, which causes the working fluid to flow along the length of the tube.
The vaporized working fluid then condenses at the cold end, releasing its latent energy and causing the cycle to repeat.
The following factors determine the heat dissipation performance of a heat pipe:
The thermal conductivity of the working fluid: The higher the thermal conductivity, the more heat the fluid can absorb and transport.
The surface area of the hot end: The greater the surface area, the more heat the fluid can absorb.
The surface area of the cold end: The greater the surface area, the more heat the fluid can release.
The diameter of the pipe: A larger diameter allows a fluid to absorb and transport more heat per unit length.
The main advantages of using a heat pipe heat sink are:
· They are very efficient at transferring heat: The thermal conductivity of the working fluid is very high, so the heat is quickly absorbed and transported to the cold end. As a result of this, the temperature difference between the hot and cold ends is minimized, thereby reducing the power consumption of the cooling device.
· They are compact and lightweight: A heat pipe's small size and low weight make it easy to transport and install.
· They are easy to use: There is no need to fill them with a working fluid or to pump it around mechanically; the natural circulation of the vaporized working fluid causes it to move along the length of the tube. Only a heat source is required at one end and a cold sink at the other.
· They are suitable for use with many different types of heat sources: As well as its natural application to electronics cooling, heat pipe technology can also be used in building and industrial process heating. They have even been used for spacecraft propulsion systems. This is because their ability to transport and dissipate heat efficiently allows them to transfer the waste heat from almost any type of heat source.
· They can be used with low-power devices: A small amount of electrical power is required to start the natural circulation of the vaporized working fluid, but this is much less than that required by mechanical pumps or fans to be used with them low-power devices.
· They have a high working temperature: The heat pipe can operate at temperatures far higher than its surroundings. This means that the heat source does not need to be cooled before it enters the heat pipe, as is necessary for most other types of cooling devices.
· They have a long service life: The vaporized working fluid efficiently transfers heat, so the device has a long service life.
1. Computers – Heat pipe heat sinks are commonly used to dissipate the waste heat generated by the CPU and graphics card.
2. Electronics – They are used in a wide range of electronic devices, including smartphones, tablets, and laptops.
3. Vehicles – Heat pipe heat sinks are used in various vehicles, including cars, trains, and planes.
4. Buildings – They are used in buildings for heating and cooling applications.
5. Industrial Processes – Heat pipe heat sinks are used in various industrial processes to dissipate waste heat.
6. Solar Energy Systems – They are used to lower the solar panel temperature in solar energy systems.
7. Telecommunications – Heat pipe heat sinks are used in telecommunications devices, such as modems, routers, and set-top boxes.
8. Refrigerators – They are also used in some types of refrigeration units that require only a small amount of cooling.
9. Marine – Heat pipe heat sinks are used in marine applications, especially for engines and generators.
10. Other Applications – Some other types of applications that require the removal or transfer of large amounts of waste heat with minimal maintenance or fan noise.