The air pressure and the air volume of the cooling fan are two relative concepts. In general, a lot of cooling fan manufacturers will consider the fan from the cost-saving aspect of the wind design, the wind will sacrifice some wind pressure. If the fan can move a lot of air, but the wind pressure is low, the wind can not reach the bottom of the radiator. On the contrary, high wind pressure often means that the wind volume is low, and there is not enough cold air to exchange heat with the radiator It's also bad for cooling. Here are some ways to share the heat transfer of a low noise DC fan. Basically any type of radiator will use the above three heat transfer methods, but the emphasis is different. 1. Heat convection refers to the heat transfer mode in which the fluid (gas or liquid) moves away the heat, and the forced heat convection mode in which the cooling fan drives the gas flow. 2. Thermal radiation refers to the heat transfer by radiation, daily is common solar radiation. The three cooling methods are not separate, in the daily heat transfer, the three cooling methods are simultaneous, combined works. For example, ordinary CPU cooling fan, CPU heat sink and CPU surface straight 3. Heat conduction, convection and radiation. When matter itself or in contact with matter, the transfer of energy is called heat transfer, which is the most common form of heat transfer. For example, the way in which the base of the CPU heatsink is in direct contact with the CPU is heat conduction. In contact, the heat of the CPU surface is transferred to the CPU heat sink by heat conduction, and the heat convection from the cooling fan takes the heat away from the surface of the CPU heat sink The flow of air in the box is also a heat convection CPU heat sink around the air away to the outside of the box, while all the high temperature parts of the surrounding low temperature will produce heat radiation. The heat dissipation efficiency of heat sink is related to the heat conductivity of heat sink material, the heat capacity of heat sink material and heat sink medium, and the effective heat dissipation area of heat sink. What is the inherent defect of DC COOLING FAN? The most widely used form is the down-blowing axial fan, which is popular because of the good and cheap combination effect. If the direction of the axial fan is reversed, it will go up, which will be used in some special types of radiators. The Cooling Fan produces turbulent flow when it is running, and the wind pressure is high, but it is easy to suffer the loss of resistance. Theoretically speaking, the heat dissipation efficiency of turbulent flow is much higher than that of Laminar flow, which has become the mainstream design form. Axial fan is widely used, but it has some inherent defects. Axial Fan by the motor position of the block, air flow can not flow through the fan area in the middle.

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