ПРОБЛЕМНІ ПИТАННЯ ТА ШЛЯХИ ЇХ ВИРІШЕННЯ ПРИ ПРОЕКТУВАННІ КОМПОЗИЦІЙНИХ ПАЛИВНИХ БАКІВ

Abstract

To reduce of the rocket constructions weight is one of the topical issues of space technology. The preliminary calculations showed that reducing the fuel tanks mass by 20 % allows to increase the cargo by 4-5% for a given launch weight, or to reduce the launch vehicle mass by about the same amount. The one of ways to solution the problem is the use of modern composite materials like a carbon fiber reinforced plastics. However, the improvement of the mass parameters exacerbates the problem of ensuring tightness of the load-bearing shell and the flange joints with the main pipelines and nozzles for supplying fuel components. This problem is especially relevant for manhole structures. The tightness in modern designs of composite fuel tanks is ensured by the load-bearing shell itself, however, the flange connections tightness, which made of composite materials, remains under the question. In the proposed work, various options for constructive and technological solutions to this problem are analysed. Considering that depressurization occurs along the joints of the flange assembly structures, the main attention is paid to the special sealants as well as to the quality of joint surfaces processing and the compensation of residual deformations by elastic elements of the seal structures. The rheological processes under the influence of external power loads should also take into account in analyzing the functionality of flange assemblies design. The proposed constructive solutions for ensure the tightness of composite fuel tanks can be used not only in the design of launch and space vehicles, but also in all areas of application of cryogenic and high-toxic chemicals.