The Development Of Dot-matrix Solar Thermal Collecting Cell

Solar thermal power generation is the important means of solar energy utilization,typically including parabolic trough,tower and dish.However,the low conversion efficiency of solar-thermal energy results in the low percentage among the total electricity output.Thus,some innovative solar thermal collecting systems need to promote the utilization efficiency.So far,many innovative researches have been applied to solar thermal collecting system,but some deficiencies still exist.Based on the advantages of the above three kinds of system,and the characteristic that the way of point-focus and cavity heating has less heat loss,this dissertation proposes dot-matrix solar thermal collecting system,and accomplishes the research of mechanical properties and optics-thermodynamics performance about the system.According to the thought of dot-matrix collecting,the system is made up of the Fresnel lens and cavity absorber.Based on the optics-thermodynamics model of system,the parameters influencing the system performance is obtained.Furtherly,the designed model of Fresnel lens with same thickness and cavity absorber are employed to complete the optics-thermodynamics simulation through the Trace Pro and ANSYS software,and the results meet theoretical requirements.The mechanical structure of dot-matrix solar thermal collecting system is designed,and the solar thermal collecting cell which is composed of four thermal collecting modules with inverted pyramid structure is employed to accomplish checking and simulation of importamt parts.Accoding to the designed tracking control and testing system,the experimental research is carried out and the results are made comparison with the theoretical analysis results.The research results show: designed dot-matrix solar thermal collecting system composed of Fresnel lens and spherical cavity absorber has simple structure,well optics-thermodynamics performance and mechanical properties;Fresnel lens has large concentration ratio and high optical efficiency,and spherical cavity absorber has good photothermal performance,which ensures the focused light is reflected and absorbed uniformly in the cavity;the experimental datas are consistent with the theoretical analysis results,solar-thermal energy conversion efficiency of the dot-matrix collecting cell reaches to 0.7,higher than the typical thermal collecting systems.From the fact,the dot-matrix solar thermal collecting system is very helpful to promote the efficiency of the solar thermal power generation.