دانلود رایگان مقاله روش حفاظت حرارتی آرایه خورشیدی برای کشتیهای هوایی استراتوسفر

abstract

Part of the sunlight energy received by the solar array on the stratospheric airship surface is converted to electric energy, and considerable energy is transformed into heat, which is bad for the envelope material and the internal pressure of the airship. It is necessary to develop different methods for the solar array to reduce its thermal effects on the stratospheric airship. Coating film, heat dissipation structure and heat insulation structure are developed to reduce the thermal effects. A series of theoretical studies are carried out to analyze the effects of three layers, especially the heat dissipation structure made up by arrayed fins, which are verified by the experimental test and CFD simulation. As for the solar array system, the mutual coordination among output power, thermal protection effect and the structure weight ought to be considered at the same time in the design of solar array system of the stratospheric airship.

5. Conclusions

(1) In order to explore the thermal protection effects of the MLTP structure, theoretical study, experimental investigation and simulation analysis are carried out in this paper. By contrasting theoretical calculation and test data, calculating method is validated for the use of equivalent conductivity. The coating film, heating dissipation and insulation layers are investigated, respectively. In addition, the specific temperature difference is defined as the ratio of the temperature difference between the top and bottom of the MLTP structure and the areal density of the solar array system with the MLTP structure. (2) It is found that the IR affects the output power by altering the thermal absorption of solar array, but by altering the photoelectric conversion efficiency for the VT. The cylindrical duct has good heat dissipation performance because of the secondary divided flow. But the poor manufacturability and high cost of the uncontinuous paper honeycomb limit its practical application. The thermal protection effect of the insulation layer increases with the increasing of its thickness, which is better than the heat dissipation layer. (3) The mutual coordination among output power, heat insulation effect and the structure weight ought to be considered at the same time in the design of solar array system of the SSA. To a certain extent, the coating film can improve the output power, but it is not obvious to reduce the heat absorption. Because the weight increasing caused by the coating film almost can be ignored, it is an alternative method. Multi-layer structure composed by heat insulation layer and heat dissipation layer can effectively reduce the heat transmission to envelope material from solar array. The structure and geometry size should be optimized to receive the best specific temperature difference in the future.