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Article
Publication date: 9 March 2015

Mohamed Khalifa, Faisal Khan and Joseph Thorp

– The purpose of this paper is to propose a quantitative model for risk-based maintenance and remaining life assessment for gas turbines.

Abstract

Purpose

The purpose of this paper is to propose a quantitative model for risk-based maintenance and remaining life assessment for gas turbines.

Design/methodology/approach

The proposed model uses historical failure and repair data from the operation of gas turbines. The time to failure of gas turbines is modeled using Weibull distribution.

Findings

The total risk is estimated considering replacement cost, repair cost, operation cost, risk of failure and turbine remaining value after a specified period of time.

Originality/value

The model is an effective tool to make optimal decisions regarding maintenance strategy (repair or replacement) and to assess the remaining life based on a comparison of the total risk. The literature review focusses on developing different models to make risk-based decisions regarding the selection of a maintenance strategy and maintenance interval, however, literature is silent regarding risk-based assessment of the equipment remaining life, which is the focus of present work. The model is tested and applied to ageing gas turbines in a cross-country pipeline.

Details

Journal of Quality in Maintenance Engineering, vol. 21 no. 1
Type: Research Article
ISSN: 1355-2511

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Article
Publication date: 11 July 2019

Mostafa Safdari Ranjbar, Tae-Young Park, Soroush Ghazinoori and Manochehr Manteghi

This paper aims to investigate the pattern of technological capability building in the gas turbine industry as a complex product system (CoPS) in an Iranian gas turbine

Abstract

Purpose

This paper aims to investigate the pattern of technological capability building in the gas turbine industry as a complex product system (CoPS) in an Iranian gas turbine producer named Oil Turbo Compressor Company (OTC) and to recognize multi-level (firm, industry and national) drivers influencing technological catching up in this company.

Design/methodology/approach

This paper used a qualitative approach and case study research strategy. A preliminary theoretical framework is proposed based on research background. Also, the data were collected from various sources, including the interview with 11 experts, studying many documents and participating in some relevant meetings and conventions. To analyze the data, the authors relied on their preliminary theoretical framework and applied the chronological sequence analysis technique.

Findings

Our findings show that, first, in contrast with mass-produced industries where capability building pattern often leads to product innovation, technological capabilities in OTC have evolved from assembling to manufacturing, upgrading and finally redesigning of existing models of gas turbines. Second, two firm-level (proper technology acquisition strategies and building organizational and managerial capabilities), two industry-level (networking, integration and collaboration among key actors and existence of local market and demand) and two national-level (government’s policies, supports and initiatives and institutional arrangement and political conditions) drivers have played indispensable roles in facilitating and accelerating technological catching up by OTC.

Research limitations/implications

Inevitably, the current research faces a few limitations. For instance, the difficulty of generalization is considered an inherent problem because it is a case study of only one Iranian latecomer company, as well as only one CoPS industry. Regarding implications, the findings suggest that technological catching up in CoPS industries in developing countries is not a simple and autonomous process and is influenced by multi-level factors, including national-, industry- and firm-level drivers.

Originality/value

In terms of theory, this paper tends to investigate and explain the catching-up process in OTC as an Iranian gas turbine producer by applying a multi-level theoretical framework that consists of firm-, industry- and national-level drivers. In terms of practice, this paper aims at investigating drivers affecting the catching-up process in a CoPS industry in a developing country that was faced with vast international sanctions, while many other studies in this area examined cases from developing countries such as Korea and China that had the opportunity of enjoying international collaborations and overseas knowledge flows.

Details

Journal of Science and Technology Policy Management, vol. 11 no. 1
Type: Research Article
ISSN: 2053-4620

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Article
Publication date: 29 July 2019

Peyman Maghsoudi, Sadegh Sadeghi, Qingang Xiong and Saiied Mostafa Aminossadati

Because of the appreciable application of heat recovery systems for the increment of overall efficiency of micro gas turbines, promising evaluation and optimization are…

Abstract

Purpose

Because of the appreciable application of heat recovery systems for the increment of overall efficiency of micro gas turbines, promising evaluation and optimization are crucial. This paper aims to propose a multi-factor theoretical methodology for analysis, optimization and comparison of potential plate-fin recuperators incorporated into micro gas turbines. Energetic, exergetic, economic and environmental factors are covered.

Design/methodology/approach

To demonstrate applicability and reliability of the methodology, detailed thermo-hydraulic analysis, sensitivity analysis and optimization are conducted on the recuperators with louver and offset-strip fins using a genetic algorithm. To assess the relationship between investment cost and profit for the recuperated systems, payback period (PBP), which incorporates all the factors is used as the universal objective function. To compare the performance of the recuperated and non-recuperated systems, exergy efficiency, exergy destruction and corresponding cost rate, fuel consumption and environmental damage cost rates, capital and operational cost rates and acquired profit rates are determined.

Findings

Based on the results, optimal PBP of the louvered-fin recuperator (147 days) is slightly lower than that with offset-strip fins (153 days). The highest profit rate is acquired by reduction of exergy destruction cost rate and corresponding decrements for louver and offset-strip fins are 2.3 and 3.9 times compared to simple cycle, respectively.

Originality/value

This mathematical study, for the first time, focuses on introducing a reliable methodology, which covers energetic, exergetic, economic and environmental points of view beneficial for design and selection of efficient plate-fin recuperators for micro gas turbine applications.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 5
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 1 May 1956

LEO WALTER

MAKERS OF STATIONARY GAS TURBINES for industrial uses claim that the lubricating cost of medium‐size power units ranges between 1 and 2% of the fuel costs. Comparative…

Abstract

MAKERS OF STATIONARY GAS TURBINES for industrial uses claim that the lubricating cost of medium‐size power units ranges between 1 and 2% of the fuel costs. Comparative figures for average Diesel engines are 5 to 10%. These savings have an effect on the total running cost economy. Detailed oil consumption figures from industrial gas turbine operators have not yet been disclosed and for similar reasons, it is not possible in this survey to discuss individual design features of all units which comprise the various lubricating systems.

Details

Industrial Lubrication and Tribology, vol. 8 no. 5
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 1 January 2014

Asis Sarkar

This paper aims to evaluate nine types of electrical energy generation options with regard to seven criteria. The analytic hierarchy process (AHP) was used to perform the…

Abstract

Purpose

This paper aims to evaluate nine types of electrical energy generation options with regard to seven criteria. The analytic hierarchy process (AHP) was used to perform the evaluation. The TOPSIS method was used to evaluate the best generation technology.

Design/methodology/approach

The options that were evaluated are the hydrogen combustion turbine, the hydrogen internal combustion engine, the hydrogen fuelled phosphoric acid fuel cell, the hydrogen fuelled solid oxide fuel cell, the natural gas fuelled phosphoric acid fuel cell, the natural gas fuelled solid oxide fuel cell, the natural gas turbine, the natural gas combined cycle and the natural gas internal combustion engine. The criteria used for the evaluation are CO2 emissions, NOX emissions, efficiency, capital cost, operation and maintenance costs, service life and produced electricity cost.

Findings

The results drawn from the analysis in technology wise are as follows: natural gas fuelled solid oxide fuel cells>natural gas combined cycle>natural gas fuelled phosphoric acid fuel cells>natural gas internal combustion engine>hydrogen fuelled solid oxide fuel cells>hydrogen internal combustion engines>hydrogen combustion turbines>hydrogen fuelled phosphoric acid fuel cells> and natural gas turbine. It shows that the natural gas fuelled solid oxide fuel cells are the best technology available among all the available technology considering the seven criteria such as service life, electricity cost, O&M costs, capital cost, NOX emissions, CO2 emissions and efficiency of the plant.

Research limitations/implications

The most dominant electricity generation technology proved to be the natural gas fuelled solid oxide fuel cells which ranked in the first place among nine alternatives. The research is helpful to evaluate the different alternatives.

Practical implications

The research is helpful to evaluate the different alternatives and can be extended in all the spares of technologies.

Originality/value

The research was the original one. Nine energy generation options were evaluated with regard to seven criteria. The energy generation options were the hydrogen combustion turbine, the hydrogen internal combustion engine, the hydrogen fuelled phosphoric acid fuel cell, the hydrogen fuelled solid oxide fuel cell, the natural gas fuelled phosphoric acid fuel cell, the natural gas fuelled solid oxide fuel cell, the natural gas turbine, the natural gas combined cycle and the natural gas internal combustion engine. The criteria used for the evaluation were efficiency, CO2 emissions, NOX emissions, capital cost, O&M costs, electricity cost and service life.

Details

International Journal of Quality & Reliability Management, vol. 31 no. 1
Type: Research Article
ISSN: 0265-671X

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Article
Publication date: 1 September 1953

D.G. Ainley

A comprehensive series of tests have been made on an experimental single‐stage turbine to determine the cooling characteristics and the overall stage performance of a set…

Abstract

A comprehensive series of tests have been made on an experimental single‐stage turbine to determine the cooling characteristics and the overall stage performance of a set of air‐cooled turbine blades. These blades, which arc described fully in Part I of this paper had, internally, a multiplicity of passages of small diameter along which cool air was passed through the whole length of the blade. Analysis of the test data indicated that, when a quantity of cooling air amounting to 2 per cent, by weight, of the total gas‐flow through the turbine is fed to the row of rotor blades, an increase in gas temperature of about 270 dcg. C. (518 deg. F.) should be permissible above the maximum allowable value for a row of uncoolcd blades made from the same material. The degree of cooling achieved throughout each blade was far from uniform and large thermal stresses must result. It appears, however, that the consequences of this are not highly detrimental to the performance of the present type of blading, it being demonstrated that the main effect of the induced thermal stress isapparently to transfer the major tensile stresses to the cooler (and hence stronger) regions of the blade. The results obtained from the present investigations do not represent a limit to the potentialities of internal air‐cooling, but form merely a first exploratory step. At the same time the practical feasibility of air cooling is made apparent, and advances up to the present arc undoubtedly encouraging.

Details

Aircraft Engineering and Aerospace Technology, vol. 25 no. 9
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 April 1996

Riti Singh

Based on a lecture prepared as part of the celebration of Cranfield University's 50th anniversary. After briefly reviewing the early years, including Cranfield…

Abstract

Based on a lecture prepared as part of the celebration of Cranfield University's 50th anniversary. After briefly reviewing the early years, including Cranfield University's entry into this technology, discusses the nature of this industry, Some of the technology drivers, including environmental concerns, are examined to provide a background against which the development and the future of the industry can be considered. This is followed by a brief survey of some of the possible new civil aero gas turbine applications over the next 50 years, both the very likely and some curiosities. Finally, the changes that are likely to occur within the industry as a result of wider economic and political trends are considered, as well as the implications for those working within the industry. The development of the civil aero gas turbine has contributed, in large measure, to today's, US$ 300 billion civil aviation industry and is rightly seen as one of mankind's major engineering achievements. A single paper cannot do justice to this industry.

Details

Aircraft Engineering and Aerospace Technology, vol. 68 no. 4
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 1 February 1946

H. Roxbee Cox

WHILE the technical part of the history of the aircraft gas turbine in Great Britain presents the features of success and failure familiar in technical progress, there is…

Abstract

WHILE the technical part of the history of the aircraft gas turbine in Great Britain presents the features of success and failure familiar in technical progress, there is another part of the history which I believe can be described as an unqualified success. I refer to the habit of collaboration which was developed between the several technical teams in my own country, between Great Britain and the United States, and, later, between Great Britain and the British Dominions.

Details

Aircraft Engineering and Aerospace Technology, vol. 18 no. 2
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 29 June 2010

S.J. Mabbutt and N.J. Simms

The use of CO2 as a replacement for conventional air in combustion gas streams of gas turbine power‐generation equipment is a novel idea and a potential method of…

Abstract

Purpose

The use of CO2 as a replacement for conventional air in combustion gas streams of gas turbine power‐generation equipment is a novel idea and a potential method of providing an almost pure CO2 stream for subsequent disposal/sequestration. The purpose of this paper is to investigate the effects of this novel gas environment on conventional gas turbine component part materials over the same range of temperatures found in service.

Design/methodology/approach

Test samples of candidate materials were tested in simulated environments using controlled gas and steam supplies to sealed horizontal laboratory furnaces. Conventional weight change tests, metal loss tests and electron microscope examination were used to assess the performance of the materials and compare the oxidation morphology. Spectra of the oxidation products were also used to determine the nature of the oxides formed on selected materials.

Findings

It is found that changes in the percentage of steam in the novel gas environment made little difference to the performance of the selected alloys. However, when the results of the program are compared with typical data from previous works, where the same alloys are exposed in air, there is a distinct trend. Comparison between the data from air exposed samples and data from those in this paper show the high CO2 environment, envisaged for the GAS‐ZEP concept, to be more aggressive to all of the alloys tested.

Originality/value

This paper describes the first investigation into the performance of candidate materials for the various components around a GAS‐ZEP system in the novel operating environments anticipated. The work has shown that current power plant materials can be considered for use in first generation GAS‐ZEP systems, but that care is required in their selection at the higher operating temperatures.

Details

Anti-Corrosion Methods and Materials, vol. 57 no. 4
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 22 March 2019

Zilai Zhang, Shusheng Zang and Bing Ge

This paper aims to develop a dynamic performance model of three-shaft gas turbine for electricity generation and to study a multi-loop control strategy of three-shaft gas

Abstract

Purpose

This paper aims to develop a dynamic performance model of three-shaft gas turbine for electricity generation and to study a multi-loop control strategy of three-shaft gas turbine for electricity generation.

Design/methodology/approach

In this paper, the dynamic performance model of the three-shaft gas turbine is established and developed. A novel approach, variable partial differential coefficient deviation linearization method is used to simulate the dynamic performance of the three-shaft gas turbine. Single-loop control system, feed-forward feedback control system and cascade system are assessed to control the engine during transient operation.

Findings

A novel approach, variable partial differential coefficient deviation linearization method is used to simulate the dynamic performance of the three-shaft gas turbine. According to the results shown, the cascade control system is most satisfactory due to its fastest response and the best stability and robustness.

Originality/value

The method of variable partial linearization is adopted to make the dynamic simulation of the model achieve higher precision, better steady state and less computation time. This paper provides a theoretical study for the multi-loop control system of a marine three-shaft gas turbine.

Details

Aircraft Engineering and Aerospace Technology, vol. 91 no. 7
Type: Research Article
ISSN: 1748-8842

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