On real-time creep damage prediction for steam turbine

In this paper, in order to solve the calculation problem of creep damage of steam turbine rotor, a real-time calculation method based on finite element model is proposed. The temperature field and stress field of the turbine rotor are calculated using finite element analysis software. The temperature data and stress data of the crucial positions are extracted. The data of temperature, pressure, rotational speed, and stress relating to creep damage calculation are normalized. A real-time creep stress calculation model is established by multiple regression method. After that, the relation between stress and damage function is analyzed and fitted, and creep damage is calculated in real-time. A creep damage real-time calculation system is constructed for practical turbine engineering. Finally, a numerical simulation experiment is designed and carried out to verify the effectiveness of this novel approach. Contributions of present work are that a practical solution for real-time creep damage prediction of steam turbine is supplied. It relates the real-time creep damage prediction to process parameters of steam turbine, and it bridges the gap between the theoretical research works and practical engineering.

The Value Of Buildings And Structures For Permafrost Damage Prediction: The Case Of Eastern Russian Arctic

The relevance of the study lay in the need to obtain reliable information on the possible economic consequences of changing geocryological conditions in the Russian Arctic, to find methods for preventing (reducing) potential damage, increasing the safety of the population and economy in the areas of the highest geocryological risks, and ensuring balanced socio-economic development in the Russian Arctic permafrost zone for the long term. The study aimed to assess the cost of fixed assets, including their most vulnerable part – buildings and structures (case study: municipalities of the Russian Arctic Asian sector). Economic sectoral structure was evaluated in accordance with the Russian Standard Industrial Classification of Economic Activities using primary statistical data – closed data from companies accounting reports. The work used statistical, cartographic, and visual-graphic methods, as well as methods for analyzing spatial information and microeconomic data. According to calculations, the Russian Arctic Asian sector concentrates the fixed assets of commercial companies with a total value of about 14.8 trillion rubles, including buildings and structures worth 10.7 trillion rubles. The obtained calculated data can be used in modeling the directions of state policy in the field of climate change adaptation and territory protection from natural hazards.

Emergency Separation Simulation and Damage Prediction of an Airliner under Wheel-Up Landing Condition

To predict the damage to and response of aircraft structures during wheel-up crash landing, numerical simulations were performed using a constitutive and damage model for ductile metallic materials developed in the ABAQUS/Explicit environment. The model of an entire aircraft and detailed submodels were established. The Johnson–Cook and Gurson material constitutive models were validated by conducting Hopkinson’s bar test. A drop hammer test and a static test of the fuse pins were performed to determine and verify the response and strength of the structure. The experimental and analytical results indicate that the stain rate and damage parameters significantly influence the emergency separation load, fuse pin strength, and separation sequence. The analysis results were compared with the test results, and a close agreement was found in terms of the maximum load and deformation.