Search academic texts

Information × Registration Number 0215U001636, 0113U004017 , R & D reports Title Development of methodology for assessing and extending the life of inhomogeneous constructions of rocket and space engineering taking into account the stress concentrators popup.stage_title Head Hudramovych Vadym Sergiyovych, Registration Date 07-04-2015 Organization The Institute of Technical Mechanics of the National Academy of Sciences of Ukraine and the State Space Agency of Ukraine popup.description2 The research subjects are non-uniform structural members with cuts for rocket-and space products. The research purpose is to analyze numerically the stressed- strained conditions and the carrying capacity considering interactions between the stress concentrators. The research methods are ones of mechanics of a deformable solid, construction mechanics, analytical and numerical techniques of computing mathematics, comparative analysis. The following results are obtained. Stressed-strained conditions of shell members of launch vehicle compartments with various cuts are established using the known projection and iteration versions of the finite-element method considering elastic strains of materials. A program for calculating the values of loads when zones of plastic strains are coming in merge together and become general ( for given geometric parameters of the structure and cuts), resulting in the drop in the carrying capability of structural members, is developed. The effects of one and several ( two and three) rectangular cuts of similar and different sizes on stressed-strained conditions of shell members of launch vehicle compartments are numerically studied depending on their sizes and l interlocations. The carrying capacity of shell members of launch vehicle compartments is analyzed.Zones of plastic strains originate locally at the edges of cuts and shell faces, coming in merge together when a load increases and the distance between cuts decreases. Versions of interactions between cuts depend on parameters of the shell and cuts. Generation of zones, which are joint for cuts, results in significantly lowering resistance of shell members of launch vehicle compartments with cuts to acting loads due to lowering in the shell stiffness. An approach to the prediction of the carrying capacity of shell members of launch vehicle compartment related to the transformation and mergence of plastic strains zones and studies of interactions between cuts is proposed. It is shown that for those problems projection-iteration versions of the finite-element method result in cutting the computer time of computations 36-45 times (depending on the class of problems) in comparison with the computing time of a traditional finite-element method (with one grid).The research results obtained at this point will be used at the subsequent stage for the development of recommendations for lowering the maximal stresses of non-uniform structural members of rocket and space technology products with the stress concentrators. Applications: rocket and space technology, machine building. Product Description popup.authors Гудрамович Вадим Сергійович Репринцев Олексій Васильович Рябоконь Сергій Андрійович Самарська Олена Вікторівна popup.nrat_date 2020-04-02 Close