Energy estimation and photometric measurements of LED lighting in laboratory
Electricity demand is prevailing all over the world now and energy management becomes very complex. This paper aims at providing solution for power demand and energy management by using HB white LED lights for domestic applications. LED lights consume very less power and gives out high energy in the form of brightness. A laboratory model is created in DIALUX 4.11 using CAD window and is illuminated with LED lights. Photometric measurements and energy evaluation are done for the laboratory model with room components of different construction materials in the presence of LED lighting. Reflectivity of different materials under illumination is determined. Simulation is done for varying brightness and calculated results are carried over to Pov-Ray 3.6 for determining the real lighting appearance of the laboratory model. Energy evaluation is done for a year and photometric values of lighting system are measured. The calculated results proves that LED lighting system can be used as an efficient lighting system for domestic purposes when compared to other lighting systems. Simulated results and photometric values of LED lighting are presented here.
Simulating the Illuminance and Efficiency of the LEDs Used in General Household Lighting
Abstract The advantage of the LEDs illumination in general household lighting was proposed. High efficiency white LED as the light source was provided the energy saving illumination of the general household lightings. Different spaces in general household with different standards of average illuminance were designed and simulated by LightTools and DIALux software. The power consumptions and efficiency of traditional illuminated light sources and LED light source in lighting the household environment were analyzed and compared with each other at the same standard of average illuminance. Finally, it provided the advantage of using white LEDs in different spaces of the general household lighting.
Effects of reservoir volume on performance of pulse tube cooler.
A pulse tube cooler has the advantages of long-life and low-vibration over conventional cryocoolers such as G-M and Stirling coolers because of the absence of moving parts at low temperature. On the other hand, the combination of a reservoir and orifice is indispensable to optimize the performance of pulse tube coolers. In order to make the pulse tube cooler compact for practical applications, the volume of reservoir should be minimized. This paper analyzes the effects of the reservoir volume on the thermodynamic performance of various components in a simple orifice and a double-inlet pulse tube cooler by combining a linearized model with a thermodynamic analysis. Expressions of entropy production for those components are presented. The results show that the reservoir volume has a significant influence on the entropy production in the various components when the reservoir to pulse tube volume ratio is smaller than about 5. The ratio is important to determine the minimum reservoir volume for a pulse tube cooler. Optimum settings for a double-inlet pulse tube cooler are also discussed.