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To ascertain energy availability and system performance, a comprehensive understanding of the systems’ degradation profile and impact on overall plant reliability is imperative. The current study presents an integrated Failure Mode and Effects Analysis (FMEA)–Markovian algorithm for reliability-based instantaneous energy performance prediction for thermal energy systems. The FMEA methodology is utilized to identify and categorize the various failure modes of the gas turbines, establishing a reliability pattern that informs overall system performance. Meanwhile, the Markovian algorithm discretizes the system into states based on its operational energy performance envelope. The algorithm predicts instantaneous energy performance according to upper and lower bounds criteria. This integrated methodology has been subjected to testing in three case studies, yielding results that demonstrate improved reliability and instantaneous energy performance prediction during system degradation. It was observed that after 14 years of operation, the likelihood of major failures increases to 79.6%, 88.7%, and 82.8%, with corresponding decreases in system performance reliability of 10.1%, 4.5%, and 7.8% for the Afam, Ibom, and Sapele gas turbine plants, respectively. Furthermore, the percentage of instantaneous mean power performance relative to the rated capacity is 37.9%, 35.1%, and 46.3% for the three gas turbine plants. These results indicate that the Sapele thermal power plant performs better relative to its rated capacity. Overall, this integrated methodology serves as a valuable tool for monitoring gas turbine engine health and predicting energy performance under varying operating conditions.

Improvement of the efficiency of modern power systems requires the development of storage technologies, optimization of operation modes, and increased flexibility. Currently, various technical solutions are used for electricity storage. The results of a literary review with an analysis of existing energy storage systems are presented, their advantages and disadvantages are considered. One of the promising solutions is the use of hydrogen as an energy storage medium. The creation of corresponding energy complexes makes it possible to obtain hydrogen by electrolysis of water, and then use it to cover peak loads. Various schemes with hydrogen-fired gas turbines with a pressure up to 35 MPa and a temperature of 1500–1700 °C were considered. The new scheme of power plant with hydrogen-fired gas turbines was synthesized, which includes a power block, hydrogen generation blocks and hydrogen and oxygen preparation unit for burning. An atmospheric electrolyzer was considered as a hydrogen and oxygen generator. For the proposed scheme, parametric optimization was performed, where the storage efficiency factor has been used as a criterion. The influence of inlet temperature in the combustion chamber, the compression rate of hydrogen and oxygen, as well as the specific energy costs of the electrolyzer were analyzed. The results of the numerical experiment were approximated in the form of polynomial dependencies, and can be used in further research on the economic efficiency of proposed power plant.

The paper considers peculiarities of operation conditions of blades of industrial and marine gas turbine plants and prospects of their development. The new nickel single-crystal high-temperature alloy is proposed for gas turbine cooled blades, which is distinguished by high structure stability and resistance to marine salt corrosion. [ABSTRACT FROM AUTHOR]

Emission sources at airports and compressor stations have the potential to emit pollutants, the effects of which can degrade local air quality. In most cases, the basis of gas pumping units includes either aircraft engines that have exhausted their flight life, or their targeted modifications to fulfill the tasks of gas pumping units and compressor stations in various gas transportation systems. The methodology for calculating the concentration of pollutants contained in the emissions of enterprises does not take into account all possible features of emission sources, in terms of passive stationary sources and cold emissions, the algorithm of the methodology requires clarification and the justifications given in the article indicate possible ways of clarification. According to the decision of the CAEP SG-2020 Coordination Meeting "detailed documentation for the Ukrainian POLEMICA air quality model provided in CAEP/12-FESG-MDG/2-WP/09 should be considered as the final documentation for verifying this model for compliance with ICAO document 9889 requirements". The results of calculating the maximum concentration for the test scenario using Gaussian models, verified in CAEP, differ by almost 2 times. A similar result according to the PolEmiCa model ~ 1.5 μg/m3 is almost two times less, which is due to the inclusion of the effects of the initial rise in the emission of the mixture from a stationary source into the algorithms of the OND-86 method. [ABSTRACT FROM AUTHOR]

The analysis of the existing gas turbine plants (GTP) by using air intercooling from various manufacturers has been carried out, the main technical characteristics and basic parameters of operation of these GTP have been determined. Among the considered technologies for intercooling of cyclic air in gas turbine plants there are data from such wellknown manufacturers as Rolls-Royce, General Electric and Nevsky Plant. The main ways of implementing intercooling of cyclic air GTP have been considered, namely, cooling in the surface heat exchanger and contact cooling with injected water. An aerothermopressor apparatus used can be a promising way of moistening the working environment of a gas turbine. The aerothermopressor work is based on the process of thermogasdynamic compression (thermopression). A feature of this process is an increase in pressure, as a result of the instantaneous evaporation of the liquid injected into the air flow, which is accelerated to speed near the sound. In this case, heat is removed from the air flow to evaporate water, as a result of which air temperature is decreased. A comparative analysis of the existing and aerothermopressor technologies for air intercooling of GTP has been carried out. The aerothermopressor provides more effective liquid spraying and, hence, more effective isothermal compression process in the high pressure compressor is done. The proposed cooling technology makes it possible using low-potential heat of secondary energy resources of gas turbine plants (heat of cyclic air). It has been revealed that the aerothermopressor allows to increase the pressure of the cyclic air between the compressors by 2-9%, which leads decreasing compression work in compressor steps, and water injection leads increasing the number of working fluid in the cycle by 2-5%, and, as a result, the power is increased by 3-10% and the GTP efficiency is increased by 2-4%. The additional amount of injected water can be up to 10-15% relative to the cyclic air consumption. [ABSTRACT FROM AUTHOR]