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Information × Registration Number 0219U100065, 0117U004447 , R & D reports Title Development of methods and means to monitor stress-strain state of hydraulic turbines, taking into account conditions popup.stage_title Head Kharchenko Yevghen V., Доктор технічних наук Registration Date 14-01-2019 Organization Lviv Polytechnic National University popup.description2 Standard industry-specific techniques for assessing the operational lifetime of power equipment are based on simple engineering formulas for shells and rods. As literary data show, calculations of structural strength for such approaches provide overestimation of the stress-strain state, which differ several times for some cases. In addition, the influence of the environment is taken into account only by the additional application of the safety factors for compensation of the heavier conditions metals work in hydrogen-containing media. On the basis of the energy destruction criterion and the constructions elements deformation model for the structural material and hydrogen-containing medium interaction conditions, the software and the methodology for the hydro turbine equipment elements workability estimating under cyclic loading and hydrogen saturation conditions, were developed in this work. The element local volume destruction energy criterion for elastic-plastic body damage level estimation during cyclic deformation has been used. The ratio of the local volume elastic-plastic deformation to its critical value was adopted as damage parameter. The material volume element failure occurs when the damage parameter reaches the 1. In order to determine the current energy of deformation of a unit of volume, as the first stage of calibration calculation, spatial geometric models are created taking into account technological material specimens of equipment formed on the surfaces of structural elements. Further, on the basis of 3D spatial analogues and using the developed in the work software, the stress-strain state of the element of construction is determined, taking into account spatial complex geometry, damage during the period of operation, repairing-renewal changes in design geometry. The thermo-physical and physical-mechanical characteristics of steels are given according to the recommendations. At the next stage, using of the developed software, the concentration   Product Description popup.authors popup.nrat_date 2020-04-02 Close