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The lumen number of LED fluorescent lamp shell is increasing rapidly. In 2006, the number of single watt lumens of mass-produced led reached 50 lumens in the early years, and this value is still increasing rapidly. The corresponding theoretical system of heat transfer was experienced in the early years, and the heat transfer techniques we can use also have a basic understanding: conduction, convection, radiation and phase change heat transfer (such as heat pipe). Therefore, on the issue of heat transfer or heat dissipation, the methods we can adopt are visible and limited.

According to the calculation relationship between luminous flux (lumen) and radiant flux (watt): km = 683 LM / W, which is the scale of luminous flux and radiant flux. In other words, the radiation flux of 1W may produce 683lm luminous flux under the most ideal condition (blackbody radiation). Therefore, even if the light efficiency of LED reaches 200lm / W, it can not convert all energy into light energy output, while others are converted into heat energy. In the long run, the heat dissipation of LED lamps will be a long-standing problem.

At present, the heat dissipation methods of LED street lamps mainly include: natural convection heat dissipation, forced heat dissipation by adding electric fans, heat pipe and loop heat pipe heat dissipation, etc. The electric fan forces the heat dissipation method system to be messy, the reliability is low, and the heat pipe and loop heat pipe heat dissipation method has high cost. The street lamp has the advantages of outdoor night use, the heat dissipation surface is located on the side and the size is limited, which is conducive to the natural convection heat dissipation of the air. Therefore, the LED street lamp proposes to choose the natural convection heat dissipation method as far as possible.

Article from: LED fluorescent tube manufacturer http://mushuren.cn/