Порівняльна високотемпературна зносостійкість сплаву ЧС88У-ВІ і стелліта Х30Н50Ю5Т2

The optimal compositions and application techniques of wear-resistant alloys on platforms of turbine blades are discussed. It is demonstrated that the serious problems arise when choosing the necessary alloying materials despite the apparent variety of them. Such a choice is significantly complicated by the lack of quantitative characteristics of wear-resistance of widely used alloying materials and basic heat-resistant alloys. Consequently, the aim of the study was to determine the quantitative comparative characteristics of wear-resistance of the ЧС88У-ВИ casting heat-resistant nickel alloy and the Х30Н50Ю5Т2 stellite at peak temperatures of gas turbine engines exploitation in the conditions most closely resembling the actual ones. It is established that the ЧС88У-ВИ alloy in the conditions of high temperature tests (~ 1150 ºС) which are close to the solution temperatures of the γ′-phase demonstrates the considerably higher resistance than the Х30Н50Ю5Т2stellite.Показано, что при кажущемся обилии наплавочных материалов при их выборе возникают серьезные проблемы. В этой связи целью исследований явилось определение количественных сравнительных характеристик износостойкости литейного жаропрочного никелевого сплава ЧС88У-ВИ и стеллита Х30Н50Ю5Т2. Установлено, что стойкость сплава ЧС88У-ВИ при температурах испытаний, близких к температурам растворения γ′-фазы значительно выше, чем стеллита.Показано, що при уявній великій кількості наплавочних матеріалів при їх виборі виникають серйозні проблеми. У цьому зв'язку метою досліджень було визначення кількісних порівняльних характеристик зносостійкості ливарного жароміцного нікелевого сплаву ЧС88У-ВИ та стеліту Х30Н50Ю5Т2. Установлено, що стійкість сплаву ЧС88У-ВИ, при температурах випробувань, близьких до температури розчинення γ'-фази, значно вища, ніж стеліту

Determining the Composition of Burned Gas Using the Method of Constraints as a Problem of Model Interpretation

This paper proposes a method for solving the problem on determining the unknown composition of a gaseous hydrocarbon fuel during its combustion in real time. The problem had been defined as the inverse, ill-posed problem. A technique for measuring technological parameters makes it possible to specify it as a complex interpretation problem.To solve it, a "library" method has been selected (selection), which is the most universal one. To implement it, a method has been constructed to compile a library in the form of a working three-dimensional array. The source data for each solution to a direct problem in the generated array are represented in the form of a single number. To this end, a position principle for recording decimal numbers has been applied.Compiling a working array employed a method for comparing the excess factor of an oxidizer and the ratio of volumetric consumption of an oxidizer and fuel. This has made it possible to apply the results from solving a direct problem on determining the temperature of combustion products in order to solve the inverse problem on determining this composition based on the measured temperature.A method has been devised for finding a solution among the elements of the working array based on the results from technological measurements of temperature of the combustion products of the burnt fuel and the ratio of the volumetric consumption of an oxidizer and fuel.The work shows the absence of errors introduced to the solution by an algorithm of the proposed method. When modeling precise technological measurements, errors are due only to the sampling of source data while solving a direct problem. The influence of measuring the technological parameters on accuracy in determining the composition of fuel has been defined. It does not exceed the magnitude that is permissible for engineering calculations.The proposed calculation method could make it possible to use under a managed mode, in energy and in the chemical industry, a large amount of hydrocarbon fuel gases that are currently considered waste. Their energy equivalent is comparable with the energy needs by the African continent