Lighting energy consumption accounts for up to 15% of the total social electricity consumption. Compared with traditional fluorescent lamps, LED lamps can save 75% of the energy, and their life is 10 times longer than the latter. Therefore, it is considered as the most promising next generation lighting technology, which is of great significance for energy saving and emission reduction. However, the luminous efficiency and lifetime of LED chips depend heavily on their working temperature. Because of their small size, high heat flux, and usually only suitable for passive cooling, the power of LED bulbs is small, so the luminous number is limited, which restricts the development of the market.

Traditionally, LED bulbs generally heat through metal parts at the bottom of the bulb, failing to make full use of the external surface heat dissipation of the lampshade, the effective heat dissipation area is small, the chip temperature is high, and the lamp life is short. Based on the in-depth study of heat dissipation characteristics of porous metal materials with different configurations, a new type of LED energy-saving lamp integrating heat dissipation and luminescence has been developed by our center through the cooperation of production, education and research with enterprises. The lattice metal bracket is placed inside the lamp, and the LED chip array is fixed on the outer surface of the bracket. The bracket and the inner surface of the lamp shade heat transfer through natural convection of gas filled in the lamp and thermal radiation between the surfaces, and heat dissipation to the environment through natural convection and thermal radiation on the outer surface of the lamp shade. Compared with traditional LED lamp, the new type of LED energy-saving lamp has obvious advantages: 1) no external heat sink is needed, which overturns the existing scheme of commercial LED lamp heat dissipation by adding metal blocks at the bottom, reduces the weight, reduces the cost by 1/3; 2) using the outer surface of the lamp shade to heat the environment, the temperature of the lamp shade is greatly increased, and the thermal conductivity area is the largest. Dahua enhances the life by 200%. 3) It realizes all-angle luminescence and increases the luminous efficiency by 20%.

Fig 4A New Integrated Light Emitting/Heat Dissipating LED Ball Bulb Lamp:

（a）Heat dissipation principle；（b）Infrared Temperature Image of Lamp Surface；

（c）CFD simulation results of flow field and temperature field in bulb；（d）sample