Development Of New High-power LED Lamp Heat Sink And Thermal Characteristics Analysis

LED(light-emitting diode), as the fourth generation of lighting source or green light source, have some features, such as energy-efficient, eco-friendly, durable, small volume and so on. Even so, it has many technical difficulties to be solved before replace the traditional lighting source completely. Among them, the problem of dissipating heat is an important factor in the development of LED. Therefore, to solve the dissipating heat of LED and proceed the optimized research has great realistic significance.First of all, I study in cylindrical radiator in the condition of large space natural convection. Through the study of the numerical simulation of cylindrical radiator, introduces the establishment of physical model, mathematical model, computational grid and boundary conditions. I study the fin interval of cylindrical radiator and the condition of the air flow, combined with the theoretical knowledge of heat transfer theory and the results of numerical simulation. Results show that there is a stagnant area between the fins and the velocity of air flow in this area is very low, almost motionless, it affects the area of effective heat radiating area. The internal of fins affects the flow condition of air between the fins, and there is a optimum value, it can makes the radiator work in the most efficient condition. So we can optimize the structure of the radiator and chang the internal of fins, and then improve the condition of air flow between the fins and improve the heat dissipation efficiency of radiator, and meet the demand of heat dissipation.Secondly, on the basis of optimizing the structure of cylindrical radiator, I study the prismatic radiator based on the numerical simulation. Without changing the geometry of the radiator and the number of fins, to study the effects of various parameters on the heat dispersion of the radiator by changing the fin spacing t, the fin thickness d and the height of radiator H. The results show that the increase of the internal of fins can improve the heat dissipating capacity, but over the certain range will cause a decline in buoyancy lift and will be unfavorable to the natural convection heat transfer, thus to select a reasonable internal between the fins is necessary. Compared to other geometric parameters, the influence of the thickness of the radiator fins to heat dispersion of the radiator is relatively small, but the thickness of the fins can’t be too thin to ensure that the fins have a certain intensity against instantaneous heat load impact. The fins with d=2mm and t=8mm get better heat dissipation effect in the four sizes to explore. The height H of the radiator effect on its heat dissipation is larger, radiator can increase the heat dissipation area and improve the heat dissipation effect when it increases. However, when the height size increases to a certain extent, the effect of improving the radiator heat dissipation effect will be no longer significantly, on the contrary, it will increase the volume, weight and economic costs.Finally, built an experimental platform and temperature measurement solutions depend on two thermal model and three structures of the smooth cylindrical and rough prism. By comparing the structure of the temperature rise of the three, it is understood that optimal design of the radiator can be considered by increasing the roughness of the fins, which can not only reduce the weight and costs, but also can improve the cooling performance of the radiator; and verify the reliability of the simulation.This paper studies the structural parameters of LED radiators, it has a good effect on guiding optimization design and production practices of LED radiators.