The role and design of the LED radiator

Update:12 Jan 2019
Summary:

The function of the LED light radiator is to absorb the […]

The function of the LED light radiator is to absorb the heat transferred from the substrate or the chip, and then radiate it to the external environment to ensure the temperature of the LED chip is normal. Most radiators are designed for natural convection and forced convection.
Usually the design of LED street light radiator is divided into the following steps:
(1) Design the outline of the LED street light radiator according to actual needs and related constraints.
(2) According to the relevant heat dissipation design criteria, the thickness, shape, spacing and thickness of the heat sink fins are optimized.
(3) Design verification and calibration calculation of the designed LED street light radiator using thermal analysis software.
Generally, the natural heat dissipation needs to consider that the temperature boundary layer is thicker during natural cooling. If the heat sink blade spacing is too small, the thermal boundaries of the two heat sink fins easily cross and affect the surface convection. Therefore, in general, the distance of the naturally cooled heat sink fins is greater than 12 mm, and if the heat sink fin height is less than 10 mm, the pitch of the heat sink fins can be confirmed according to the heat sink fin pitch of not less than 1.2 sheets. Because the heat transfer capability of the surface of the heat sink of the natural cooling method is weak, the increase of the ripple on the surface of the heat sink fin does not have too much influence on the natural convection effect, so the surface of the heat sink fin does not need to add too much ripple, and phosphorus can be used. The treatment is applied to the surface of the heat sink for anti-corrosion treatment, and the radiation coefficient of the heat-dissipating surface can be increased to enhance the radiation heat exchange. It is also important to note that since natural convection reaches a relatively long thermal equilibrium time, the substrate and the slab of the natural convection heat sink should be thick enough to withstand the impact of transient thermal loads.