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1

Gas turbine vibration monitoring based on real data and neuro-fuzzy system

Nail Bachir, Djaidir Benrabeh, Tibermacine Imad Eddine, Napoli Christian, Haidour Nabil, Abdelaziz Rabehi

Diagnostyka

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2024

|

Vol. 25, No. 1

art. no. 2024108

EN

The gas turbine is considered to be a very complex piece of machinery because of both its static structure and the dynamic behavior that results from the occurrence of vibration phenomena. It is required to adopt monitoring and diagnostic procedures for the identification and localization of vibration flaws in order to ensure the appropriate operation of large rotating equipment such as gas turbines. This is necessary in order to avoid catastrophic failures and deterioration and to ensure that proper operation occurs. Utilizing an approach that is based on spectrum analysis, the purpose of this study is to provide a model for the monitoring and diagnosis of vibrations in a GE MS3002 gas turbine and its driven centrifugal compressor. This will be done by utilizing the technique. Following that, the collection of vibration measurements for a model of the centrifugal compressor served as a suggestion for an additional method. This method is based on the neuro-fuzzy approach type ANFIS, and it aims to create an equivalent system that is able to make decisions without consulting a human being for the purpose of detecting vibratory defects. In spite of the fact that the compressor that was investigated has flaws, this procedure produced satisfactory results.

2

Optimization sealing and cooling to control gas intrusion in a floating-wall combustion chamber

Shi Hong, Wang Rui, Chen Mingmin, Wang Jiao, Yuan Jie, Zhang Qianwei, Yang Kaijie

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2024

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Vol. 72, nr 2

art. no. e148834

EN

In response to the problems of high-temperature gas intrusion and ablation in the expansion slit between ceramic tiles under complex flow conditions in the floating-wall combustion chamber, as well as the issue of hooks exceeding their service temperature, numerical simulations and analysis were conducted for this paper. The study revealed the mechanisms of gas intrusion and sealing and proposed two evaluation metrics for evaluating the cooling effect: the maximum temperature of the hook and the proportion of high-temperature area on the sidewall of the tile. Furthermore, the CRITIC weighting method was used to analyze the weight of these metrics. Based on this, the spacing, radius, and length effects on sealing and cooling effectiveness were studied, and multi-parameter calculations and optimization were performed. The results showed that the degree of gas intrusion in the transverse slit was significantly higher than that in the longitudinal slit. In addition, the sealing method of the jet impingement could effectively cool the downstream of both the transverse and longitudinal slit. The spacing of the jet impingement holes had the greatest impact on the cooling effect, followed by the radius and length. Finally, when the spacing of the holes is 10 mm, the length is 18.125 mm, and the radius is 1.6 mm, the cooling effect is optimal, with the proportion of high-temperature area on the side wall of the tile being 20.86% and the highest temperature of the hook reaching 836.02 K.

3

Reduction of CO2 emissions from offshore combined cycle diesel engine-steam turbine power plant powered by alternative fuels

Olszewski Wojciech, Dzida Marek, Nguyen Van Giao, Cao Dao Nam

Polish Maritime Research

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2023

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nr 3

71--80

EN

Diverse forms of environmental pollution arise with the introduction of materials or energy that exert adverse effects on human health, climate patterns, ecosystems, and beyond. Rigorous emission regulations for gases resulting from fuel combustion are being enforced by the European Union and the International Maritime Organization (IMO), directed at maritime sectors to mitigate emissions of SOx, NOx, and CO2. The IMO envisions the realisation of its 2050 targets through a suite of strategies encompassing deliberate reductions in vessel speed, enhanced ship operations, improved propulsion systems, and a transition towards low and zero-emission fuels such as LNG, methanol, hydrogen, and ammonia. While the majority of vessels currently depend on heavy fuel or low-sulphur fuel oil, novel designs integrating alternative fuels are gaining prominence. Technologies like exhaust gas purification systems, LNG, and methanol are being embraced to achieve minimised emissions. This study introduces the concept of a high-power combined ship system, composed of a primary main engine, a diesel engine, and a steam turbine system, harnessing the energy contained within the flue gases of the main combustion engine. Assumptions, constraints for calculations, and a thermodynamic evaluation of the combined cycle are outlined. Additionally, the study scrutinises the utilisation of alternative fuels for ship propulsion and their potential to curtail exhaust emissions, with a specific focus on reducing CO2 output.

4

ARMAX-based identification and diagnosis of vibration behavior of gas turbine bearings

Mahroug Youcef, Khaldi Belgacem Said, Guemana Mouloud, Hafaifa Ahmed, Iratni Abdelhamid, Colak Ilhami

Diagnostyka

|

2023

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Vol. 24, No. 3

art. no. 2023310

EN

Parametric identification approaches play a crucial role in the control and monitoring of industrial systems. They facilitate the identification of system variables and enable the prediction of their evolution based on the input-output relationship. In this study, we employ the ARMAX approach to accurately predict the dynamic vibratory behavior of MS5002B gas turbine bearings. By utilizing real input-output data obtained from their operation, this approach effectively captures the vibration characteristics of the bearings. Additionally, the ARMAX technique serves as a valuable diagnostic tool for the bearings, enhancing the quality of identification of turbine variables. This enables continuous monitoring of the bearings and real-time prediction of their behavior. Furthermore, the ARMAX approach facilitates the detection of all potential vibration patterns that may occur in the bearings, with monitoring thresholds established by the methodology. Consequently, this enhances the availability of the bearings and reduces turbine downtime. The efficacy of the proposed ARMAX approach is demonstrated through comprehensive results obtained in this study. Robustness tests are conducted, comparing the real behavior observed through various probes with the reference model, thereby validating the approach.

5

Dependence between nominal power deterioration and thermal efficiency of gas turbines due to fouling

Herdzik Jerzy

Zeszyty Naukowe Akademii Morskiej w Szczecinie

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2022

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nr 69 (141)

45--53

EN

Deterioration in the performance of gas turbines is a well-known phenomenon occurring during their operation. The most important form is a decrease in the internal efficiency of the compressor and turbine due to fouling, which is the most significant deterioration problem for an operator. This article presents the effect of gas turbine fouling as a drop in airflow, pressure ratio, and compressor efficiency resulting in a reduction in power output and thermal efficiency. This resulted in a decrease in the nominal power of a gas turbine and an increase in the fuel consumption (heat rate). The fouling effects were described using the example of the MT30 marine gas turbine with a nominal power of 36 MW. The estimated profit loss during the operation of the gas turbine was within the range of 1–10% of the total fuel consumption cost. A 2% deterioration in the output of a gas turbine accounted for US$ 10,000–20,000 per year and 1 MW of gas turbine nominal power (according to marine fuel prices in 2019–2020) – this means at least US$ 300,000 annually for an MT30. Due to the low accuracy of fuel consumption measurements, another possibility was provided. The correlation between the gas turbine power deterioration and thermal efficiency was presented, which made it possible to estimate the increase in the specific and total fuel consumption when the nominal power deterioration is known. Two linear approximations were proposed to calculate increases in the annual operating costs for an MT30 due to fouling.

6

Investigation of the characteristics of a low-emission gas turbine combustion chamber operating on a mixture of natural gas and hydrogen

Serbin Serhiy, Burunsuz Kateryna, Chen Daifen, Kowalski Jerzy

Polish Maritime Research

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2022

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nr 2

64--76

EN

This article is devoted to the investigation of the characteristics of a low-emission gas turbine combustion chamber, which can be used in Floating Production, Storage and Offloading (FPSO) vessels and operates on a mixture of natural gas and hydrogen. A new approach is proposed for modelling the processes of burning out a mixture of natural gas with hydrogen under preliminary mixing conditions in gaseous fuel with an oxidizer in the channels of radial-axial swirlers of flame tubes. The proposed kinetic hydrocarbon combustion scheme is used in three-dimensional calculations for a cannular combustion chamber of a 25 MW gas turbine engine for two combustion models: the Finite-Rate/Eddy-Dissipation and the Eddy Dissipation Concept. It was found that, for the investigated combustion chamber, the range of stable operations, without the formation of a flashback zone in the channels of radial-axial swirlers, is determined by the hydrogen content in the mixture, which is less than 25-30% (by volume). For the operating modes of the chamber without the formation of a flashback zone inside the swirler channels, the emissions of nitrogen oxide NO and carbon monoxide CO do not exceed the values corresponding to modern environmental requirements for emissions of toxic components by gas turbine engines.

7

Technological methods of ensuring the reliability of lock connections in marine gas turbines

Dvirna Olha, Zembrzuska Natasza

Journal of KONBiN

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2022

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Vol. 52, iss. 3

149--163

EN

The article presents the test results of the surface quality parameters after broaching of heat-resistant steels of grades: 1.7335 (13CrMo4-5) and 1.4841 (X15CrNiSi25-20). The aim of the work is to determine the technological methods of obtaining the lowest treated surface roughness, surface layer hardening and the elimination of surface defects after broaching. To investigate the influence of cutting conditions (cutting speed, tool geometry and feed) on surface roughness and hardness, the physical modeling method of the broaching was used. As a result of the research, recommendations for improvement of the main parameters of the surface layer quality when broaching samples from selected grades of heat-resistant steels.

PL

W artykule przedstawiono wyniki badań parametrów jakości powierzchni po przeciąganiu stali żaroodpornych gatunków: 1.7335 (13CrMo4-5) i 1.4841 (X15CrNiSi25-20). Celem pracy jest określenie technologicznych sposobów uzyskania najmniejszej chropowatości obrobionej powierzchni, korzystnego poziomu umocnienia warstwy wierzchniej i eliminacji defektów powierzchniowych po obróbce skrawaniem. Aby zbadać wpływ warunków skrawania (prędkości skrawania, geometrii narzędzia i prędkości posuwu) na chropowatość i umocnienia powierzchni, zastosowana została metoda modelowania fizycznego procesu przeciągania. W wyniku badań opracowane zostały rekomendacje dotyczące podniesienia głównych parametrów jakości warstwy wierzchniej podczas przeciągania próbek z wybranych gatunków materiałów żaroodpornych.

8

Insight into Damping Sources in Turbines

Moneta Grzegorz

Fatigue of Aircraft Structures

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2022

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Iss. 14

69--82

EN

Blade vibrations in aircraft engines are a significant challenge that must be overcome during the design and development of modern turbine engines. Vibrations lead to cyclic displacements and result in alternating stress and strain in undesired environments (high temperatures, erosion, corrosion of the surface, etc.). Under resonance conditions, stress amplitudes can increase and exceed their safety limits, and in extreme cases, can lead to engine failure. One method to reduce resonance vibrations is to increase damping in the turbine assembly. This paper presents and describes vibration damping sources in the turbine, including aerodynamic, material, and friction damping. Additionally, typical damping values for each damping component are presented and compared.

9

Gas turbine reliability estimation to reduce the risk of failure occurrence with a comparative study between the two-parameter Weibull distribution and a new modified Weibull distribution

Djeddi Ahmed Zohair, Hafaifa Ahmed, Iratni Abdelhamid, Kouzou Abdellah

Diagnostyka

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2022

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Vol. 23, No. 1

no. art. 2022107

EN

Responding to the needs of quality and robustness of analysis and management of degradation of equipment, to increase their life cycle and to expand these facilities to become more and more sophisticated and agronomic. This work proposes a contribution to increase the survival of a gas turbine, installed in a gascompression plant, with a comparative study between the two-parameter Weibull distribution. A new modified Weibull distribution was proposed also to reduce the risk of occurrence of failure in this rotating machine. A Statistical analysis and validation on the synthesis of turbine's reliability data and failures were considered, with a particular focus on the use of this data to increase the availability of this type of machine. So, developing a maintenance plan based on their reliability indices for scheduled inspections.

10

Turbine stage expansion model including internal air film cooling and novel method of calculating theoretical power of a cooled stage

Trawiński Paweł

Archives of Thermodynamics

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2022

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Vol. 43, no 3

3--27

EN

Systematic attempts to maximise the efficiency of gas turbine units are achieved, among other possibilities, by increasing the temperature at the inlet to the expansion section. This requires additional technological solutions in advanced systems for cooling the blade rows with air extracted from the compressor section. This paper introduces a new mathematical model describing the expansion process of the working medium in the turbine stage with air film cooling. The model includes temperature and pressure losses caused by the mixing of cooling air in the path of hot exhaust gases. The improvement of the accuracy of the expansion process mathematical description, compared with the currently used models, is achieved by introducing an additional empirical coefficient estimating the distribution of the cooling air along the profile of the turbine blade. The new approach to determine the theoretical power of a cooled turbine stage is also presented. The model is based on the application of three conservation laws: mass, energy and momentum. The advantage of the proposed approach is the inclusion of variable thermodynamic parameters of the cooling medium. The results were compared with the simplified models used in the literature: separate Hartsel expansion, mainstream pressure, weighted-average pressure and fully reversible. The proposed model for expansion and the determination of theoretical power allows for accurate modelling of the performance of a cooled turbine stage under varying conditions.

11

Repairability analysis of the energy gas turbine rotor blade second stage shroud by high-temperature brazing

Klimczuk Piotr

Welding Technology Review

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2021

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R. 93, nr 2

23--31

EN

The article considers the repair of the energy gas turbine rotor blade second stage shroud. The paper presents an analysis of the possibility of the repair consisting of the replacement of both labyrinth and honeycomb seals by the high-temperature brazing process. All the steps of the repair process were discussed and the results of microscopic metallographic evaluation using a light microscope and a scanning electron microscope were presented. SEM BSE microstructure and elements distribution of the joints has been presented. Several advantages related to the use of this technology were indicated.

PL

W artykule omówiono tematykę regeneracji osłony łopatki wirnika drugiego stopnia energetycznej turbiny gazowej. Przedstawiono analizę możliwości jej naprawy polegającej na wymianie zarówno uszczelnień labiryntowych jak i ulowych z zastosowaniem procesu lutowania wysokotemperaturowego. Omówiono poszczególne etapy procesu naprawy oraz zaprezentowano wyniki badań metalograficznych mikroskopowych z użyciem mikroskopu świetlnego oraz elektronowego mikroskopu skaningowego. Wskazano na szereg korzyści związanych ze stosowania tej technologii.

12

Bezpośrednie wykorzystanie gazów wylotowych z turbiny gazowej w przemyśle przetwórczym – przegląd zastosowań i możliwości wdrożenia na polskim rynku

Cichocki Marek, Salamonik Ilona, Bielecki Marcin, Fadlun Ever, Rusowicz Artur

Rynek Energii

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2021

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Nr 5

68--77

PL

Klasyczne układy ze skojarzonym wytwarzaniem energii elektrycznej i ciepła wymagają wprowadzenia dodatkowego medium grzejnego. Alternatywnym rozwiązaniem jest bezpośrednie wykorzystanie gazów wylotowych z silnika cieplnego. Dzięki wysokiej temperaturze oraz znacznym strumieniem ciepła w stosunku do mocy, gazy wylotowe z turbiny Gazowej (TG) zostały z powodzeniem zastosowane w skali przemysłowej jako: podgrzane powietrze w piecach przemysłowych, źródło ciepła do bezpośredniego osuszania oraz w absorpcyjnych urządzeniach chłodniczych. W artykule zawarto przegląd udokumentowanych zastosowań TG w przemyśle przetwórczym z uwzględnieniem uwarunkowań technicznych i ekonomicznych, jak również, kryteria doboru TG. Opisane rozwiązania pozwoliły na obniżenie energochłonności w zakresie od 7% do 20% oraz redukcję kosztów zużywanej energii na poziomie 15-30%. Redukcja energochłonności obniża ilość emitowanego CO2. Osiągnięto także całkowitą sprawność układów kogeneracji powyżej 90%. Dokonano również wstępnej oceny możliwości integracji gazów wylotowych dla TG produkowanych przez Baker Hughes w polskim przemyśle.

EN

The typical combined heat and power plants require the introduction of additional heating medium. The alternative solution is the direct integration of the exhaust gases from heat engine. High temperature and high exhaust energy to power ratio, enabled the integration of Gas Turbine (GT) exhaust gases at industrial scale as: preheated combustion air for industrial furnaces, heat source for direct drying and for absorption chillers. The article comprises the review of documented applications of GTs with direct exhaust gas integration in the process industry focusing on technical and economic considerations, as well as GTs selection criteria. The described solutions allowed to reduce specific energy consumption by 7-20% or the costs of energy consumption by 15-30%. The reduction of specific energy consumption allows to decrease the amount of CO 2 emitted. The overall efficiency of cogeneration plant above 90% was achieved. The preliminary feasibility assessment of the opportunities to integrate exhaust gases in the polish industry for the Gas Turbines produced by Baker Hughes is done.

13

Parametric analysis of the efficiency of the combined gas-steam turbine unit of a hybrid cycle for the FPSO vessel

Serbin Serhiy, Washchilenko Nikolay, Dzida Marek, Kowalski Jerzy

Polish Maritime Research

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2021

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nr 4

122--132

EN

A thermal diagram of the combined gas‒steam turbine unit of a hybrid cycle, which is an energy complex consisting of a base gas turbine engine with a steam turbine heat recovery circuit and a steam-injected gas turbine operating with overexpansion, is proposed. A mathematical model of a power plant has been developed, taking into consideration the features of thermodynamic processes of simple, binary, and steam-injected gas‒steam cycles. Thermodynamic investigations and optimization of the parameters of a combined installation of a hybrid cycle for the generation of electrical energy have been carried out. Three-dimensional calculations of the combustion chamber of a steam-injected gas turbine were carried out, which confirmed the low emissions of the main toxic components.

14

Duże turbiny gazowe umożliwiające zastosowanie wodoru

Klebes Jurgen

Nowa Energia

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2021

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nr 2

90--92

PL

Rezygnacja z paliw kopalnych na rzecz zastosowania wodoru stanowi skuteczną opcję i jest niezbędna dla zapewnienia zrównoważonego rozwoju dostaw energii. Mitsubishi Heavy Industries Ltd. (MHI) wspiera badania i rozwój dużych turbin gazowych, które najpierw umożliwią używanie mieszaniny gazu ziemnego i wodoru, a najpóźniej od 2030 r. - wyposażone w nowy suchy palnik o niskiej emisji NOx - będą pozwalały również na pracę w trybie zasilania samym wodorem. Projekt ten realizowany jest przy wsparciu organizacji New Energy and Industrial Technology Development Organization (NEDO), partnera współuczestniczącego w pracach badawczo-rozwojowych.

15

Efficiency analysis of the aerothermopressor application for intercooling between compressor stages by using CFD model

Kobalava Halina, Radchenko Mykola, Konovalov Dmytro

Journal of New Technologies in Environmental Science

|

2021

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Vol. 5, nr 4

129--134

EN

A study of the aerothermopressor operation for air intercooling between the stages of a multistage compressor as part of a modern gas turbine (LMS100 brand from General Electric) was carried out in the article. A calculation method has been developed using numerical modeling for the evaporation of fine water droplets in the air flow. The main characteristics of the two-phase flow at the aerothermopressor outlet have been determined. It has been found that jet apparatus provides efficient atomization of the liquid, and hence, more efficient isothermal compression process in a high-pressure compressor. The aerothermopressor applying allowed to reduce the temperature of the compressed air between the compressor stages to 50-70°C. Such a decrease in temperature under the thermo-gas-dynamic compression conditions allowed to increase the pressure at the aerothermopressor outlet up to 12-28 kPa (4-9%).

16

The analysis of the impact of environmental factors on turbine performance, develpoment of the models relating the periods between maintenances with selected maintenance factors

Thielmann Magdalena

Inżynieria Bezpieczeństwa Obiektów Antropogenicznych

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2021

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Nr 3

1--10

EN

There are currently around 18,000 commissioned Gas Turbines in use worldwide, with almost 7,500 long-term service agreements. At the same time, orders for new units increase year by year, and after a decrease in production in 2020 from 353 to 328 new units, from 2022 onwards, the level is planned to rise to the previous level of growth. Gas turbines operate worldwide and are exposed to variations in environmental conditions, such as changes in humidity, temperature, and salinity, which can significantly affect the efficiency and faster degradation of individual components. Based on the unit's maintenance report, there are more than 1,940 event alerts annually. A need exists to create a more dynamic analytical and numerical model that determines the impact of environmental variables on gas turbine stability. It is necessary to analyze and improve existing reliability models, which vary due to configurations and the impact of working conditions. The first step should be an analysis of the impact of environmental factors on turbine performance. This paper describes how the maintenance and inspection model developed from an average value over time model to a model tracking the actual degradation of gas turbines. It includes a comparison ofthree models used in the research, considering the developed methodology for selecting input parameters, their correlation, and their appropriateness for use in further analyses.

17

Insight Into Vibration Sources in Turbines

Moneta Grzegorz, Jachimowicz Jerzy, Pietrzakowski Marek, Doligalski Adam, Szwedowicz Jarosław

Fatigue of Aircraft Structures

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2021

|

Iss. 13

40--53

EN

Despite of nearly 100 years of turbine engine development and design, blade vibrations remain a great engineering challenge. The rotating turbine blades’ vibrations lead to cyclic oscillations, which result in alternating stress and strain in harsh environments of high temperature and pressure. In modern aeroengines, high hot flow velocities might generate erosion and corrosion pitting on the metal surfaces, that leverage remarkably mean stresses. The combination of both mean and alternating stresses can lead to unexpected engine failures, especially under resonance conditions. Then, alternating stress amplitudes can exceed the safety endurance limit, what accelerates the high cyclic fatigue leading quickly to catastrophic failure of the blade. Concerning the existing state-of-the-art and new market demands, this paper revises forced vibrations with respect to excitation mechanisms related to three design levels: (i) a component like the blade design, (ii) turbine stage design consisting of vanes and blades and (iii) a system design of a combustor and turbine. This work reviews the best practices for preventing the crotating turbine and compressor blades from High Cyclic Fatigue in the design process. Finally, an engine commissioning is briefly weighed up all the pros and cons to the experimental validations and needed measuring equipment.

18

Predictive modelling of turbofan engine components condition using machine and deep learning methods

Matuszczak Michał, Żbikowski Mateusz, Teodorczyk Andrzej

Eksploatacja i Niezawodność

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2021

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Vol. 23, no. 2

359--370

EN

The article proposes an approach based on deep and machine learning models to predict a component failure as an enhancement of condition based maintenance scheme of a turbofan engine and reviews currently used prognostics approaches in the aviation industry. Component degradation scale representing its life consumption is proposed and such collected condition data are combined with engines sensors and environmental data. With use of data manipulation techniques, a framework for models training is created and models' hyperparameters obtained through Bayesian optimization. Models predict the continuous variable representing condition based on the input. Best performed model is identified by detemining its score on the holdout set. Deep learning models achieved 0.71 MSE score (ensemble meta-model of neural networks) and outperformed significantly machine learning models with their best score at 1.75. The deep learning models shown their feasibility to predict the component condition within less than 1 unit of the error in the rank scale.

19

Wybrane zagadnienia przepływowe turbiny gazowej pracującej w tłoczni gazu ziemnego

Grzymkowska Anna

Dozór Techniczny

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2021

|

z. 6

12--14

PL

W niniejszym artykule przedstawiono cieplno-przepływowe obliczenia turbiny gazowej, stanowiącej napęd sprężarki w tłoczni gazu ziemnego. Wartości parametrów wejściowych niezbędnych do przeprowadzenia obliczeń przyjęto na podstawie danych technicznych tłoczni zasilających polski odcinek gazociągu tranzytowego Jamał-Europa, w których pracują turbiny gazowe SGT-600 firmy Siemens, o mocy 25,3 MW.

20

Theoretical analysis of LNG regasifier supplementing gas turbine cycle

Szczygieł Ireneusz, Rutczyk Bartłomiej Paweł

Archives of Thermodynamics

|

2021

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Vol. 42, no 4

47--67

EN

Liquefied natural gas (LNG) is transported by the sea-ships with relatively low pressure (0.13–0.14 MPa) and very low temperature (about 100 K) in cryo-containers. Liquid phase, and the low temperature of the medium is connected with its high exergy. LNG receives this exergy during the liquefaction and is related with energy consumption in this process. When the LNG is evaporated in atmospheric regasifiers (what takes place in many on-shore terminals as well as in local regasifier stations) the cryogenic exergy is totally lost. fortunately, there are a lot of installations dedicated for exergy recovery during LNG regasification. These are mainly used for the production of electricity, but there are also rare examples of utilization of the LNG cryogenic exergy for other tasks, for example it is utilized in the fruit lyophilization process. In the paper installations based on the Brayton cycle gas turbine are investigated, in the form of systems with inlet air cooling, liquid phase injection, exhaust gas based LNG evaporation and mirror gas turbine systems. The mirror gas turbine system are found most exegetically effective, while the exhaust gas heated systems the most practical in terms of own LNG consumption.