Antifreeze Method Of Flat Plate Solar Collectors

The solar water heating systems are the practical technique products that are widely used, and have the very maturely technique and notably effects in the industry that make use of the solar thermal technology. The flat-plate solar collector in common used has the vast development foreground because of the good pressure suffering ability, the simple structure and the cost-effective, and a unique combination with buildings.Much change along with the global weather, extreme weather will often happen in the warm tropical regions. The general types of flat-plate solar collector do not have the antifreezing functions, so it will be frozen in the case of low-temperature weather. It is very necessary to study the Heat-absorbing solar power batteries as the kernel components of the flat-plate solar collectors.After a comprehensive comparison of various freezing methods, making the use of flat tube-type collector structure would be a good solution to flat-plate collector of a freeze. It has advantages of structure simply, the force better, cost-effective high.Freeze test found that the tubes would be destroyed when freeze, and mainly caused by the circumferential stress. Aim at the pipe when the water completely frozen, and through the adoption of certain assumptions, gained the formula of water freeze expansion in the pipe, can be used to calculate the expansion force when the water is completely freezen in the pipe, the formula is as follows:The analysis result by ANSYS was consistent with the calculation results.The sequence of radial ice analysis by ANSYS software with elliptical tube, flat tube, diamond-shaped and 8 character tube, Show that at the radial sequence from the wall to the center are the order of the freezing characteristics. According to the characteristics in the follow-up studies on the structures and materials of tube, the freezing force is simulated as an analog pressure, so the analytical process is simplified.The materials which the type of flat panel collector commonly used now are the 0Cr18Ni9, T2 and the material 5A05.Through the comparison of three Materials of profiled tube on the pressure suffering capacity and deformation capacity respectively, the material 5A05 is the best in use.Through analysis of ANSYS software on the capacity of the pressure suffering and deformation separately, found the best tube shapes from a variety of tube, and carried out separately analog ANSYS analysis of the freezing. The results show that the elliptical tube has good pressure suffering and deformation capacity. On this basis we further analysis of the thickness on the capacity of the antifreeze. Combining the results of previous, found that the best structure, materials and thickness antifreezed profiled tube flat-plate solar collectors.