Concentrating Performance Study Of Solar Dish And Experiment Research Of Air Receiver

The solar power system includes the dish solar thermal power generation system,the tower solar thermal power generation system,the parabolic through solar thermal power generation system and the linear Fresnel-type solar thermal power generation system.The dish solar thermal power generation system consists of the dish,receiver and generating system.The dish and the receiver are the key components of the whole system.Its optical and thermal efficiency determine the conversion efficiency of the whole dish solar thermal power generation system directly.In this paper,by building a solar dish test platform,the dish concentrating performance test and the air receiver operating characteristic test are carried out respectively under the actual solar radiation.In the concentrating performance test of the solar dish,a solar dish with the diameter of12.5 meters was used as the research object.A water-cooled Lambertian plate was used as the receiving plane.The CCD camera was used to take pictures of the Lambertian plate.The flux distribution image was obtained through image processing.The measurement results show that the actual focal length of the solar dish is smaller than the designed focal length;the maximum concentration ratio of the dish is 932 with the average concentration ratio of 331.The optical efficiency of the dish is 81.39%.A Monte Carlo method was used to establish the concentrating model of the solar dish.The mode was verified with experiment data.The total energy collected on the Lambertian plane through simulation,which was 7.74% different from the experiment result,and the maximum flux density was 1.03% different from the experiment result.The overall flux distribution was close,but the spot shape was slightly different.A method for adjusting the dish was proposed,and the feasibility of the method for adjusting the solar dish was verified using the developed model.By adjusting the solar dish,the maximum concentrating ratio of the solar dish can be increased to 3628,and the adjustment effect is obvious.The influence of cavity shape on the flux distribution inside the cavity are carried out based on the proposed model.In the operating test of the air receiver,a coil-type air receiver was used as the research object,and the related experiments were carried out on the solar dish to explore the relationship among the temperature,mass flow rate and pressure loss.The results show that the air receiver can heat the air from the ambient temperature to above 600 ? in 10?20 minutes.In the test,the maximum outlet temperature of the air receiver is 836 ?,which has reached the operatingtemperature of the air Brayton cycle.The air receiver has a certain thermal inertia,when the DNI(Direct Normal Irradiance)drops suddenly,the outlet temperature of air receiver changes small which is beneficial to the operation of the power generation system.