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Abstract One factor that significantly limits blade service life and reliability in GT-100 power turbines is sulphide-oxide metal corrosion of guide and rotating blades. Application of coatings is the most efficient method to prevent corrosion failure. An electron beam physical vapour deposition CoCrAlY coating is used for high and low pressure turbine first-stage rotating blades made from E1 893 alloy. Studies of CoCrAlY-coated blades after different service periods (from 390 to 5900 h) showed that this coating most efficiently protects rotating blades in turbines which operate in northern regions of the country. Because of low temperature hot corrosion leakage, corrosion failure is observed in turbines operating in southern regions of the country. In order to improve corrosion resistance, a ceramic coating has been developed. These coatings increase the endurance of equipment and make it possible to save energy.

The paper proves the economic feasibility of using a local autonomous source of energy supply, which is formed from electrical equipment of other functional purposes based on an asynchronous machine with capacitive self-excitation. To assess the technical and economic indicators of the effectiveness of introducing a local autonomous source of energy supply, the discounted method is adopted, where an indicator of savings from possible losses due to the exclusion of labor resources from production is used as an additional influence factor.

For the evaluation of the detection and measurement limits for gamma-spectrometry measurements formulas were elaborated assuming the presence of the background component, which correlates with the analytical peak in the sense of: (1) linear relation between the expectation value of the peak and background counts, and (2) statistical correlation between peak and background counts. It is shown that neglecting the correlated background component can lead to a significant overestimation of the detection and measurement limits. The problem of evaluating of the correlated background component by applying experimental and computational approaches is also considered.

We consider a method aimed at the determination of the rate of atmospheric corrosion in metallic structures according to the polarization resistance based on the use of multielectrode sensors with cosurface location of the electrodes (applied to increase the sensitivity of measurements). The serviceability of four models of electrochemical sensors intended for the monitoring of metallic structures under the conditions of atmospheric corrosion for an atmospheric humidity of 100 % and temperatures of 24, 40, 50, and 70°C is investigated. It is shown that, by decreasing the thickness of the insulating interlayer, the width of electrodes, and their number, it is possible to increase the accuracy and sensitivity of measurements of the corrosion rate in humid atmospheres. The developed sensors prove to be suitable for the purposes of monitoring of the corrosion rate in metallic structures operating under the atmospheric conditions, including closed volumes.

Today, incentive policies have been proposed to contribute to small consumers in the market to improve network security. In this paper, the simultaneous competition of small consumers in the form of independent firms and power plants in the new market structure is modeled and the impact of competition of these firms on the behavior of generation firms and network costs is investigated. Given the multiplicity of consumer presence in this market and the rumor that this may slow down the market settlement process, the effect of imposing restrictions on a strategy change for all participants has been investigated.

Abstract This paper presents the results of experimental study of the pool boiling process for the nanofluids isopropyl alcohol (isopropanol)/Al2O3. The test experiments on pool boiling of the isopropanol (C3H8O) and refrigerant R11 (CCl3F) were conducted to verify the reliability of developed experimental setup. The experimental values of the determined heat transfer coefficients and bubble departure diameters have been compared with several models reported in the literature. An effect of Al2O3 nanoparticles on the heat transfer coefficient and bubble departure diameter during isopropanol boiling was measured and analysed. Moreover, the experiments for determination of the isopropanol contact angle on the bare surface and surface coated by nanoparticles after nanofluid boiling have been performed in order to evaluate its effect on the boiling process. Finally, obtained experimental data for the heat transfer coefficient of isopropanol, refrigerant R11 and nanofluids isopropanol/Al2O3 using RPI heat flux partitioning model have been fitted with an uncertainty less than 10%.