When the heat is transferred to the top of the radiator, it is necessary to dissipate the transferred heat to the surrounding environment as soon as possible. For air-cooled radiators, it is necessary to exchange heat with the surrounding air. At this time, the heat is transferred between two different media. The formula to follow is Q=α X A X △T. It‘s the temperature difference between the two media, that is, the temperature difference between the radiator and the surrounding air; and a is the heat conduction of the fluid. The coefficient, after the heat sink material and air composition are determined, it is a fixed value; the most important A is the contact area between the heat sink and the air, under the premise of the same other conditions, such as the volume of the heat sink will generally vary Restrictions, the space in the case is limited, too much will increase the difficulty of installation, and by changing the shape of the radiator, increasing its contact area with the air, increasing the heat exchange area, it is an effective means to improve the heat dissipation efficiency. To achieve this, the surface area is generally increased by using fin-type design supplemented by surface roughening or threading.
When the heat is transferred to the air, the temperature of the air in contact with the heat sink will rise rapidly. At this time, the hot air should be as far as possible to take away the heat with the surrounding cold air through heat exchange methods such as convection. For air-cooled radiators The most important method is to increase the speed of air flow and use a fan to achieve forced convection. This point is mainly related to the design of the fan and the wind speed. The efficiency of the radiator fan (such as flow rate, wind pressure) mainly depends on the fan blade diameter, axial length, fan speed and fan blade shape. The flow rate of the fan mostly adopts CFM as the unit (English system, cubic feet/minute), and a CFM is about 0.028mm3/minute flow rate.
Aluminum radiator is the most common radiator in the early stage. Its manufacturing process is simple and low in cost. So far, aluminum radiator still occupies a considerable part of the market. In order to increase the heat dissipation area of its fins, the most commonly used processing method for aluminum radiators is aluminum extrusion technology. The main indicators for evaluating an aluminum radiator are the thickness of the radiator base and the Pin/Fin ratio. Pin refers to the heat sink. The height of the fin, Fin refers to the distance between two adjacent fins. The Pin/Fin ratio is the height of Pin (excluding the thickness of the base) divided by Fin. The larger the Pin-Fin ratio, the larger the effective heat dissipation area of the heat sink, and the more advanced the aluminum extrusion technology.