Views: 96 Author: Site Editor Publish Time: 2019-09-24 Origin: Site
Heat pipe heatsink is a new product which can make great changes by using heat pipe technology. There are two kinds of heat pipe radiators: natural cooling and forced air cooling. The thermal resistance value of air-cooled heat pipe heatsink can be smaller, which is often used in high-power power supply.
The heat pipe heatsink consists of a sealed tube, a suction core and a steam passage. The suction core is surrounded by the wall of the sealed pipe and is immersed with saturated liquid which can be volatilized. The liquid can be distilled water, ammonia, methanol or acetone, etc. Heat pipe heatsinks filled with liquid such as ammonia, methanol and acetone still have good heat dissipation capability at low temperature.
When the heat pipe heatsink runs, its evaporation section absorbs the heat generated by the heat source. Then it boils the liquid in the core tube into steam. Steam with heat moves from the evaporation section to its cooling section. When the steam passes heat to the cooling section, the steam condenses into liquid. The condensated liquid is returned to the evaporation section through the capillary action, thus repeating the above-mentioned circulation process to continuously dissipate heat.
Heat pipe heatsink is a kind of high efficiency heat dissipation device, which has unique heat dissipation characteristics. It has high thermal conductivity. The temperature distribution is uniform and basically equal.
The thermal resistance of the heatsink is determined by the thermal conductivity of the material and the effective area in the volume. When the volume of solid aluminium or copper heatsink reaches 0.006m³, the thermal resistance can not be significantly reduced by increasing its volume and area. For the discrete semiconductor devices with two-sided heat dissipation, the thermal resistance of air-cooled all-copper or all-aluminum radiators can only reach 0.04 ℃/W. The cast heatsink can reach 0.01 ℃/W. Under the condition of natural convection cooling, the performance of heat pipe heatsink can be improved more than ten times than that of solid radiator.
Heat pipe heatsinks have the following advantages:
(1) The thermal response is fast, and its heat transfer capacity is more than 1000 times larger than that of copper tubes of the same size and weight.
(2) It is small in size and light in weight.
(3) It can simplify the heat dissipation design of electronic equipment, such as changing air-cooling to self-cooling.
(4) No additional power supply is needed and no special maintenance is needed during work.
(5)It has good isotherm. After heat balance, the temperature gradient of evaporation and cooling section is quite small, which can be approximately considered as 0.
(6)The operation is safe and reliable, and does not pollute the environment.
(1) It has low vapor flow viscous force.
(2) The shearing force of droplet dispersal is caused by the excessive vapor velocity, which exceeds the surface tension of the liquid.
(3) Fluid flow is greater than capillary transport capacity. This phenomenon dries the capillary and destroys the catheter easily.
(4) When all fluids reach boiling vaporization, the heat transfer capacity will be reduced.
In practical application, the heat transfer speed of extrusion heatsink is relatively fast, and the heat resistance value can be reduced and the heat dissipation efficiency can be increased after the matching equipment is installed. It has a high position in certain industries.
