A serisi katı hal aydınlatma teknolojileri için pasif ısıl yönetimin sınırları

Energy has been one of the most important problems for the last few decades. Efficient use of energy is as important as efficiency in energy production and transportation. Solid state lighting (SSL) technology may reduce consumed energy in buildings from 20 percent to less than 5 percent. Light emitting diodes (LEDs) have recently been evolved as a novel lighting technology that is over 7-10 times more efficient than conventional-old incandescent lamps. Although LED lighting systems have many other advantages as being more reliable and having longer lifetimes than conventional energy lighting systems like environmentally hazardous fluorescent lamps, they are based on solid state technology with thermal limitations. Low junction temperature requirement is one of the most important challenges for the high luminosity LED lighting systems, which also have high heat generation rates. Junction temperature of LEDs is directly related with reliability, lifetime, light output and quality. Therefore, thermal management is crucial for LED lighting systems. Passive thermal management of LED lighting systems has many advantages as simplicity, reliability, low cost and silent operation. Nevertheless high cooling capacity requirement means large passive cooling components, which push the limits of the form factor standards. Besides the size and weight limitations, tight interaction between thermal management and optical design obligate researchers to develop all components in a compact system. In this study, different passive air-cooling thermal management systems for high luminosity A-line LED lamps are investigated. Commercial A-line LED bulbs with various passive cooling approaches and designs are experimentally studied in order to bring thermal, optical and dimensional limitations of passively cooled A-line SSL systems into view. A new system level passive thermal management approach based on buoyancy driven chimney effect is computationally developed. The optical design of the system is also computationally developed at the same time. All computational results are validated with the experimental results. Computational and experimental results of the developed and manufactured system are analyzed, and the system is computationally optimized. Finally, several figure of merits (FOMs) are developed for SSL systems for the advancement of science and technology. Thus, various commercially available bulbs and developed prototypes are compared to bring various design options into view.