Thermal cooling system of laptop
In the thermal cooling module of laptop, the three key elements are heat pipe, heat dissipation fan and heat dissipation fin. In addition, there are elements used to improve the contact area and heat conduction efficiency between them.
Many notebooks are covered with a layer of copper heat sink on the surface of chips such as CPU, GPU, video memory and power supply module. As the "intermediary" between the chip and the heat pipe, its primary task is to quickly "extract" the heat from the chip. It also has the effect of increasing the contact area and expanding the cooling area.
In fact, there is a layer of thermal conductive grease as a filler between the chip and the heat sink, and between the heat sink and the heat pipe. At the same time, the surfaces of the heat sink and the heat pipe should also be finely polished - the surfaces of the copper heat sink and the heat pipe are generally very rough, otherwise it will affect their full contact with the thermal conductive grease.
The heat pipe is a hollow metal pipe made of pure copper. The part in contact with the cpu/gpu chip is the "evaporation end", and the part in contact with the cooling fin is the "condensation end". The heat pipe is filled with condensate (such as pure water). Its working principle is that the high temperature on the chip surface will convert the liquid at the evaporation end of the heat pipe into steam (the boiling point is very low in vacuum), and move along the pipe cavity to the tail of the heat pipe (the condensation end).
For the design of laptop cooling module, the coarser the diameter and the more the number of heat pipes, the higher the heat conduction efficiency. However, in order to reduce the hot steam in the condensation section of the heat pipe to liquid in the shortest time, higher requirements are also put forward for the matched cooling fins.
Cooling fins are classified as "passive cooling elements" in the field of electronic engineering design. They are mainly made of aluminum and copper. Their working principle is to dissipate the heat transferred from the heat pipe in the form of convection. The cooling efficiency depends on the size of the surface area.
In the process of "cpu/gpu → thermal conductive silicone grease → heat sink → heat pipe", the heat dissipation journey of the notebook has reached half, and the next step is how to "eliminate" the heat outside the body.The use of cooling fan can take away all the heat from the CPU or GPU components by force air cooling , which makes the laotop wrok in a stable temperature.
It should be noted that, except for a few notebooks that adopt fan free design and pursue extreme lightness, the cooling fins cannot exist independently. A group of cooling fins must correspond to a cooling fan and a corresponding cooling air outlet.
