Addres: Xialang Industry Area, No.19 Dongguan Road,Qishi Area,Dongguan,China
Scan QR code:
Improved thermal design in order to minimize the overall thermal resistance of the led diving flashlight, that is, reduce the number of thermal resistance, some way, proposed in the literature summarized in the following two:
Integrated package of the film - to cancel the metal PCB board to generate insulating film and the electrode film on a metal radiator, the cooling effect will be far superior to conventional metal PCB board, to further reduce the overall thermal resistance of the led diving flashlight.
Radiator directly on the chip package is to cancel the conventional led torch internal heat sink, while the chip package in the pre-designed metal cooling surface with a special structure, the overall package. In this way also be able to further reduce the thermal resistance.
2.2.3led diving flashlight passive cooling solution
Passive cooling of the led torch is mainly applied to medium and small power led torch cooling. Since no additional consumption of electricity, so the application of the overall efficiency is not affected.
(1) Natural cooling
Natural cooling works to the outside of the substrate with the heat sink by heat conduction is to export high-calorie chips, and then through convection with the air exchange heat off the radiator.
Thermal conductivity of the basic formula:
Where, Q is the heat is the heat of the thermal conductivity; K the thermal conductivity of the material, the higher the thermal conductivity is also lower than the value of the heat; A heat transfer area (or the contact area of two objects) ; Ends of the temperature is difference; ΔL for both ends of the distance. Therefore, from the formula can be found, the size of the heat transfer and thermal conductivity, thermal heat transfer area, both the temperature proportional to the difference, the same is inversely proportional to the distance. Radiator materials with high thermal conductivity, its temperature rise to low, specific heat, usually made of high thermal conductivity and heat capacity of materials (copper, aluminum) (see Table 1).
Thermal convection of the basic formula:
Where Q is heat, that is, the heat away by convection; H for the heat convection coefficient; A thermal convection of the effective contact area; ΔT temperature difference between the solid surface and the regional fluid. Thermal convection pass, the size of the heat transfer with the heat convection coefficient, the effective contact area and temperature difference is proportional to. In order to increase the cooling effect, an increase of the contact area of the surface and the air the outer surface of the radiator can be made of fin shape. The shape of the fins is also varied, and the number of fins, location, size, tilt angle and thickness and so needs to be carefully studied, in addition to the common linear, there are wavy, spiral, cylindrical and cone Taiwan-shaped, etc., to name a few, the purpose is to facilitate the air flow, rainfall, and to get the best cooling effect. On the materials used, the thermal conductivity of copper is much faster than the aluminum, copper heat no aluminum, which will form a new type of copper-aluminum composite heat sink - combine the advantages of copper and aluminum respective , copper can quickly led diving flashlight chips, high-calorie pass aluminum, the heat dissipated by the large area of the aluminum fins, so as to achieve more good cooling effect.