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Документ Creep and damage in shells of revolution under cyclic loading and heating(Elsevier Ltd., 2014) Breslavsky, D.; Morachkovsky, O.; Tatarinova, O.Creep of cyclically loaded thin shells of revolution and their fracture due to creep and fatigue mechanisms are studied. Creep-damage equations for steels and nickel-based alloys are built by the use of scalar damage parameter. Constitutive equations were derived using the method of asymptotic expansions and averaging over a period of cyclic loading. The cases of fast and slow varying of temperature and loading are regarded. General problem statement and method for solution of creep problems at cyclic loading are presented. Strain–stress state in shell structures is determined by the use of homemade FEM creep–damage code, where the finite element of conical shell is used. Results of creep–damage problem for conical panel are discussed.Документ Creep damage processes in cyclically loaded structural members(Serbian Chamber of Engineers, 2012) Breslavsky, D.; Morachkovsky, O.The paper contains the description of the cyclic creep damage law that allows to estimate the long-term strength of metallic materials in wide range of frequencies of loading and heating. Asymptotic methods and procedures of averaging in a period were used for deriving the damage laws.Документ Cyclic creep damage in thin-walled structures(Mechanical Engineering Publications, Ltd., 2000) Altenbach, H.; Breslavsky, D.; Morachkovsky, O.; Naumenko, K.Thin-walled structural elements are often subjected to cyclic loadings. This paper presents a material model describing creep behaviour under high-cycle loading conditions (N greater than or equal to 5 x 10(4)-10(5)). Assuming that the load can be split into two joint acting parts (a static and a superposed, rapidly varying small cyclic component), the asymptotic expansion of two time-scales has been applied to the governing equations of the initial-boundary value creep problem. The system of equations determine two problems. The first is similar to the creep problem by quasi-static loading. The second is the problem of forced vibrations. Both the problems are coupled by constitutive equations. The model is applied to the simulation of the cyclic creep damage behaviour of thin-walled structural elements. The results are discussed for two special numerical examples (a conical shell and a circular plate). The simulations show that the creep and the damage rates as well as the failure time are strongly sensitive to the redistribution of the stress state cycle asymmetry parameter A(s). The values of A(s) increase during the creep process. For particular cases of the loading frequency, A(s) can exceed the critical value. In this case the material model must be extended in order to consider the creep-fatigue damage interaction.Документ Estimation of heat field and temperature models of errors in fiber-optic gyroscopes used in aerospace systems(Технологический центр, 2017) Breslavsky, D.; Uspensky, V.; Kozlyuk, A.; Pashchenko, S.; Tatarinova, O.; Kuznyetsov, Yu.Розроблено та досліджено чисельно-аналітичні моделі теплового нестаціонарного процесу та пов'язаної з ним похибки вимірювань волоконно-оптичних гіроскопів (ВОГ). З урахуванням значень температури, отриманих шляхом моделювання, а також результатів калібрування конкретних ВОГ, побудовано прогнози величин похибок вимірювань. Проведено порівняння результатів моделювання з експериментальними даними. Наведено рекомендації з розвитку результатів та їхнього практичного використання.Документ High temperature creep and damage accumulation in cyclically loaded axisymmetrical bodies of revolution(National Technical University "Kharkov Polytechnic Institute", 2010) Breslavsky, D.; Korytko, Yu.; Morachkovsky, O.The paper presents the constitutive equations as well as the data of numerical simulation of creep-damage problems of cyclically loaded and heated axisymmetrical structural members. The procedure of constitutive equations deriving is discussed. The experimental and numerical data have been obtained for cyclically heated specimens made from high quality steel were compared in order to verify the flow rule and damage parameter equation. The problem of creep and damage accumulation in the nipples of the regenerator for catalytic cracking of petroleum was analyzed with consideration of different temperature cycle parameters.Документ A new model of nonlinear dynamic creep(Kluwer Academic Publishers, 1995) Breslavsky, D.; Morachkovsky, O.Документ Numerical Calculations of Creep Damage at Cyclic Loading by Use of Tensor Damage Parameter Model(Точка, 2013) Breslavsky, D.; Korytko, Yu.; Mietielov, V.; Morachkovsky, O.; Tatarinova, O.Creep of cyclically loaded bodies and their fracture due to creep mechanisms are studied. Creep damage equations are built by use of tensor parameter for titanium alloy. Similar equations were derived for stress cyclic varying using the method of asymptotic expansions and averaging in a period. 2d plane stress problems were solved by FEM and fields of stress, strain, displacement, damage parameter components as well as time to rupture values were obtained