The New Cpc Vacuum Tube Type Solar Collector Simulation Study

The paper analyzes the present situation of our country’s energy use, not renewable energy consumption and serious environmental pollution, this time the development and use of renewable clean energy already is imminent. Solar energy as clean energy has value in utilization, because it has more merits, such as extensive, environmental protection and permanent characteristics. Good conditions for use solar energy in China with abundant solar energy resources, which is the basis of this study.The key technology in the utilization of solar collector is turn radiation energy into heat energy. Due to the solar energy much decentralized, collect the solar energy is the main job. The core component of the solar utilization is solar collectors, it is a special device used to turn the solar radiation energy into heat energy and then transfer heat to working fluid.This project has established CPC solar collector mathematical model in order to provide the theoretical foundation of the thermal performance for itself. CPC solar collector is more complicate than normal sollar collector. It includes three different heat transfer ways which consists of three heat transfer methods:heat conducting, heat convection, radiation heat transfer. This paper will introduce the solar radiatoion, heat loss of solar collector, energy balance of solar collector and flow resistance of collector system. The mathmatical model is helpful for design the solar collector. CPC evacuated tubular solar collector integrate the compound parabolic and the evacuated tubular technology, designing new receiver as an innovation. The receiver is composed of brass tube and glass tube, between of the vacuum, brass with fin. The other innovation is that the selective coating was covered on the surface of the brass pipe and the fins, not on the surface of inner pipe of the evacuated tubular as before.Firstly, according to the location of KunMing, the solar radiation intensity in KunMing was obtained. Secondly, compound parabolic concentrator was studied in this thesis. The system equation of the compound parabolic was obtained; compound parabolic concentrator model was establishment, and saving cost. The research shows that the lower focusing and the lower total mirror height, the consumption of mirror surface treatment material is less, the cost will be greatly reduced. Finally, according to the basic principles of heat transfer, the heat transfer model of new CPC evacuated tubular solar collector was proposed. The efficiency of the CPC collector is deduced factor, fin-root efficiency, total heat loss coefficient, heat transfer and the instantaneous efficiency equation and so on. Instantaneous efficiency equation of this collector is η=0.65-1.22(Tf-Ta)/(I·CR), as well as the relationship of the instantaneous collector efficiency of CPC evacuated tubular solar collector and the temperature difference of the fluid.The calculated results indicated that new CPC evacuated tubular solar collector fully played the advantages of enhancing energy density after focusing, meanwhile it is easy to combine with the construction in KunMing, therefore there will be great potential for CPC evacuated tubular solar collector in the future.