Investigation of the Influence of Thermal and Climate Effects on the Performance of Tiled Thermal Protection of Spacecraft

The article discusses the thermal protection of spacecraft under various types of thermal and climatic influences. During the pre-launch preparation, several types of icing are possible on the surface of the tiled structure, consisting of quartz heat-shielding tiles. It is very important in the process of operation, to determine normal and shear stresses during icing and the impact of ice formed in the tile gaps. It is necessary to calculate the strength and performance of the tiled thermal protection in active stages of flight of spacecraft. A mathematical model was constructed that allows, with a sufficient degree of accuracy, to research the tiled structure for strength, shear and tearing of the tile when exposed to ice. Calculations for strength, shear, and tearing of tiles under the influence of ice were performed. Theoretical and experimental studies were compared. The performed calculations made it possible to show that the tile will not collapse under the considered load. The strength of the substrate withstands the emerging shear forces. The values of the adhesion strength of ice appearing on the surface of quartz fiber heat-protective coating were obtained. It was demonstrated that the proportion of tangents in the stressed state of the tile does not exceed 10%. The proposed mathematical model for studying the characteristics of the tiled thermal protection of a spacecraft adequately describes the processes under study. Experimental studies have shown satisfactory agreement with theoretical results. The calculations performed to determine the ultimate shear stresses in the substrate showed that the strength of the substrate withstands the emerging shear forces. Consideration of climatic conditions can significantly reduce risks in the design of thermal protection of modern aircraft. The results of this study can be used in further studies, and they can also be taken into account in the construction of aircraft.