Experimental and simulation research on a vacuum tube used for the trough concentrator

Experimental measurement and simulation analysis of a U-type direct flow vacuum tube which can be used for the trough concentrator have been completed in this paper. The U-type vacuum tube has been measured in a new multi-surface concentrator and all experiments have been done in actual weather, contrast experiments of traditional direct flow vacuum tube have also been carried out, the temperature curves of the water which is heat by the two different vacuum tube and efficiency curves of two different heating system have been given respectively, according to the curves, difference of the two temperature curves and the two efficiency curves have been explained. The heat transfer process and temperature field of the two vacuum tubes has been analyzed by way of numerical simulation, according to the results of analysis, inside cross-sectional views of the two vacuum tubes have been obtained and the temperature curves of the water which goes across vacuum tube have been drawn. At last, the factors which relative to efficiency of vacuum tube have been figured out and some plans to improve the efficiency of the U-type direct flow vacuum tube have been submitted.