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[Display omitted] • Theoretical and run-test evaluation of the 50 MW beam-down power plant is conducted. • The variation in heliostat efficiency, flux density, and power generation is analyzed. • The average outlet temperature of the molten salt was up to 559℃ for 50 min. • The flux density of hyperboloid mirror on four typical days is 10.2/11.2/10.9/9 kW/m2. • The flux density of receiver on four typical days is 353.6/399.1/381.7/314.2 kW/m2. The beam-down concentrating solar power plant has the advantages of high concentrating ratio, low installation and maintenance requirements, and low pump consumption. To conduct further theoretical and run-test evaluations of the optical and thermal performance of the beam-down concentrating solar power system, the Yumen Xinneng 50 MW beam-down power plant is analyzed in this research. The variation of the heliostat field efficiency, hyperboloid mirror flux density, receiver flux density, and annual power generation under various operating parameters is discussed. The run-test results from June 12th indicated an average outlet temperature of molten salt reached 559°C between 13:07 and 13:56 under an average direct normal irradiation of 739.7 W/m2. The corresponding inlet temperature increased from 302.3°C to 307.6°C due to the rewarming effect caused by the increase in hot molten salt. Regarding the simulation results, the recommended design parameters for the vertex ratio of the hyperboloid mirror are between 0.775 and 0.8 to mitigate the contradiction between initial investment and optical efficiency. The maximum values of cosine efficiency, shading and blocking efficiency, shading efficiency of the hyperboloid mirror, and attenuation efficiency for the heliostat field are 85.56%, 99.96%, 99.35%, and 97.46% on June 1st for the maximum solar elevation angle of 70.72°. Consequently, the maximum values of the average hyperboloid mirror flux density and receiver flux density are 11.2 kW/m2 and 399.1 kW/m2 on June 1st. The maximum power generation for a 7-day period is 4674.22 MWe in June with a duration time of 100 hours. This paper can further expand research on the comprehensive performance of beam-down power plants. [ABSTRACT FROM AUTHOR]

Heliostats are prone to be destroyed under the action of thunderstorm and hail in the wild. Many studies on heliostat mainly focused on the effect of wind load, while it is a lack of in-depth understanding on the dynamic responses of heliostats under hail impacting. This study performs the dynamic response of heliostat under hail impacting in Tibetan Plateau of China by numerical simulation. A hail dynamic constitutive model considering strain rate effect and brittle fracture behavior was established and verified based on historical hail statistics, and the effects of hail impacting position, hail size, elevation angle and thickness of heliostat on the dynamic response characteristics were analyzed. The research results demonstrate that the impact position has a significant influence on the displacement of heliostat, but a little effect on the maximum stress. The stress and displacement of the heliostat increase with the increase of hail size, while decrease with the increase of the elevation angle and thickness of heliostat. When the hail diameter increases to 30 mm, the maximum principal stress of heliostat exceed its tensile strength. The results are useful and interesting to researchers who can reference the obtained results to predict the heliostat safety under hail impacting. [ABSTRACT FROM AUTHOR]

Abstract: The focus of the current study is the wind loads on a 10.5 m × 9.0 m heliostat with a column height of 6.4 m, located in Beijing, PR China. This paper presents selected results of wind tunnel measurements of wind pressures on the heliostat. Wind pressure distributions are presented for typical configurations. Fluctuating wind pressure characteristics are analyzed, including skewness and kurtosis coefficients, fluctuating pressure spectra and probability density functions. [Copyright &y& Elsevier]

Abstract: DAHAN, the pioneer 1MWe CRS (central receiver system) funded by Ministry of Sciences and Technology (MOST), which can be regarded as the milestone in solar thermal power development in China, is now under construction at the foot of The Great Wall nearby Beijing. The major objective of the design and construction of DAHAN is to demonstrate the operation of CRS in China. A software tool HFLD is developed for heliostat field layout design and performance calculation. The simulation results from HFLD approximately agree very well with the published heliostat field efficiency data from Spain PS10. Based on that, the heliostat field layout of DAHAN is designed using HFLD and the whole CRS performance is simulated in the TRNSYS plant model. The modeling and simulation of this plant is presented in this paper. [Copyright &y& Elsevier]