| 1. |
- Celis, Cesar, et al.
(författare)
-
Multidisciplinary Design Optimization of Aero Engines : Environmental Performance-Based Methodology
- 2008
-
Ingår i: SYMKOM’08 Proceedings. CIEPLNE MASZYNY PRZEPLYWOWE. TURBOMACHINERY. No.133.
-
Konferensbidrag (refereegranskat)abstract
- A methodology and tool that allows evaluating and quantifying aero engines design trade-offs originated as a consequence of addressing conflicting objectives such as low environmental impact and low operating costs is presented, and applied to a general case study to assess the feasibility of using new highly efficient engine configurations: intercooled- recuperated (ICR) engines. The case study results show that according to the ICR systems performance (heat exchangers effectiveness, pressure losses, and weight penalty) they could find usage in practical applications.
|
|
| 2. |
- Khan, Raja S.R., et al.
(författare)
-
An Assessment of the Emissions and Global Warming Potential of Gas Turbines for LNG Applications
- 2009
-
Konferensbidrag (refereegranskat)abstract
- This paper concentrates on the emissions module of what is part of a wider project dealing with various aspects of gas turbine usage as drivers for Liquefied Natural Gas (LNG) production. The framework is known as TERA, a Techno-Economic and Environmental Risk Analysis, developed at Cranfield University with the core of the study being the performance module whilst the risk, economics and environmental modules are built around the performance. Whilst TERA exists for aviation and power production no such system is available for assessment of LNG production.With mounting pressures by the way of emissions taxes, new legislation is imminent, especially in Europe. This will mean Oil & Gas firms will have to look for ways to improve their emissions in order to avoid such taxes. One way to reduce turbomachinery losses is to replace dated machinery. The selection of turbomachinery involves assessments of risk, both economic and technical, as well as environmental impacts of the new
|
|
| 3. |
- Khan, R.S.R., et al.
(författare)
-
An Assessment of the Emissions and Global Warming Potential of Gas Turbines for LNG Applications
- 2009
-
Ingår i: ASME TURBO EXPO 2009 Proceedings, ASME-GT-2009-59184.
-
Konferensbidrag (refereegranskat)abstract
- This paper concentrates on the emissions module of what is part of a wider project dealing with various aspects of gas turbine usage as drivers for Liquefied Natural Gas (LNG) production. The framework is known as TERA, a Techno-Economic and Environmental Risk Analysis, developed at Cranfield University with the core of the study being the performance module whilst the risk, economics and environmental modules are built around the performance. Whilst TERA exists for aviation and power production no such system is available for assessment of LNG production. With environmental issues high on the public agenda new legislation on emissions can be expected, especially in Europe. This will mean Oil & Gas companies will have to look for ways to reduce their emissions. One way to reduce turbo machinery losses is to replace out dated and/or obsolete machinery having less overall energy efficiency. The selection of turbomachinery involves assessments of risk, both economic and technical, as well as environmental impacts of the new technology. The core to all of this is the performance assessment, the primary basis on which selection is made. An aviation emissions model, developed at Cranfield University, is adapted for industrial applications. Technical performance calculations are made using the inhouse software called Turbomatch. Performance results for three typical days of the year (summer, winter and spring/autumn) are fed into the emissions model to get the levels of NOx, CO2, H2O, CO and unburnt hydrocarbon emissions. Later, NOx, CO2 and H2O emissions levels are fed into the environmental module to estimate the damage the engine causes to the environment over 100 years with respect to global warming. Two hypothetical engine configurations are investigated based on engine data available in the public domain. The first one, an 85MW single spool industrial machine (SSI-85), is used as the baseline to compare against a 100MW triple spool, intercooled aeroderivative (ITSA-100). The results suggest that the ITSA-100 produces more NOx but has less carbon emissions and consequently less global warming effects. This has varied economic impacts depending on which emission is a priority for reduction. CO2 and H2O emissions are more important than NOx for LNG gas turbine applications. The paper shows how this simple but effective system can be utilised to give a viable comparison between one or more proposed solutions for turbomachinery selection and replacement. The scope of the system is expanded as other modules come together to give a total assessment in terms of technical, economic, environmental and risk perspectives for LNG production.
|
|
| 4. |
- Kyprianidis, Konstantinos, et al.
(författare)
-
Assessment of Future Aero Engine Designs with Intercooled and Intercooled Recuperated Cores
- 2010
-
Ingår i: ASME TURBO EXPO 2010 Proceedings, ASME-GT-2010-22519. - 9780791843987 ; 3, s. 909-920
-
Konferensbidrag (refereegranskat)abstract
- Reduction in CO 2 emissions is strongly linked with the improvement of engine specific fuel consumption, as well as the reduction in engine nacelle drag and weight. Conventional turbofan designs, however, that reduce CO 2 emissions—such as increased overall pressure ratio designs—can increase the production of NO x emissions. In the present work, funded by the European Framework 6 collaborative project NEW Aero engine Core concepts (NEWAC), an aero-engine multidisciplinary design tool, Techno-economic, Environmental, and Risk Assessment for 2020 (TERA2020), has been utilized to study the potential benefits from introducing heat-exchanged cores in future turbofan engine designs. The tool comprises of various modules covering a wide range of disciplines: engine performance, engine aerodynamic and mechanical design, aircraft design and performance, emissions prediction and …
|
|
| 5. |
- Kyprianidis, Konstantinos G., et al.
(författare)
-
EVA : A Tool for EnVironmental Assessment of Novel Propulsion Cycles
- 2008
-
Ingår i: <em><em></em></em>ASME Turbo Expo 2008: Power for Land, Sea, and AirVolume 2: Controls, Diagnostics and Instrumentation; Cycle Innovations; Electric PowerBerlin, Germany, June 9–13, 2008. - 9780791843123 - 0791838242 ; , s. 547-556
-
Konferensbidrag (refereegranskat)abstract
- This paper presents the development of a tool for EnVironmental Assessment (EVA) of novel propulsion cycles implementing the Technoeconomical Environmental and Risk Analysis (TERA) approach. For nearly 3 decades emissions certification and legislation has been mainly focused on the landing and take-off cycle. Exhaust emissions measurements of NOx, CO and unburned hydrocarbons are taken at Sea Level Static (SLS) conditions for 4 different power settings (idle, descent, approach and take-off) and are consecutively used for calculating the total emissions during the ICAO landing and take-off cycle. With the global warming issue becoming ever more important, stringent emissions legislation is soon to follow, focusing on all flight phases of an aircraft. Unfortunately, emissions measurements at altitude are either extremely expensive, as in the case of altitude test facility measurements, or unrealistic, as in the case of direct in flight measurements. Compensating for these difficulties, various existing methods can be used to estimate emissions at altitude from ground measurements. Such methods, however, are of limited help when it comes to assessing novel propulsion cycles or existing engine configurations with no SLS measurements available. The authors are proposing a simple and fast method for the calculation of SLS emissions, mainly implementing ICAO exhaust emissions data, corrections for combustor inlet conditions and technology factors. With the SLS emissions estimated, existing methods may be implemented to calculate emissions at altitude. The tool developed couples emissions predictions and environmental models together with engine and aircraft performance models in order to estimate the total emissions and Global Warming Potential of novel engine designs during all flight phases (i.e. the whole flight cycle). The engine performance module stands in the center of all information exchange. In this study, EVA and the described emissions prediction methodology have been used for the preliminary design analysis of three spool high bypass ratio turbofan engines. The capability of EVA to radically explore the design space available in novel engine configurations, while accounting for fuel burn and global warming potential during the whole flight cycle of an aircraft, is illustrated.
|
|
| 6. |
- Kyprianidis, Konstantinos G.
(författare)
-
Multi-Disciplinary Conceptual Design of Future Jet Engine Systems
- 2010
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis describes various aspects of the development of a multi-disciplinary aero engine conceptual design tool, TERA2020 (Techno-economic, Environmental and Risk Assessment for 2020), based on an explicit algorithm that considers: engine performance, engine aerodynamic and mechanical design, aircraft design and performance, emissions prediction and environmental impact, engine and airframe noise, and production, maintenance and direct operating costs.As part of this research effort, a newly-derived semi-empirical NOx correlation for modern rich-burn single-annular combustors is proposed. The development of a numerical methods library is also presented, including an improved gradient-based algorithm for solving non-linear equation systems. Common assumptions made in thermo-fluid modelling for gas turbines and their effect on caloric properties are investigated, while the impact of uncertainties on performance calculations and emissions predictions at aircraft system level is assessed. Furthermore, accuracy limitations in assessing novel engine core concepts as imposed by current practice in thermo-fluid modelling are identified.The TERA2020 tool is used for quantifying the potential benefits from novel technologies for three low pressure spool turbofan architectures. The impact of failing to deliver specific component technologies is quantified, in terms of power plant noise and CO2 emissions. To address the need for higher engine thermal efficiency, TERA2020 is again utilised; benefits from the potential introduction of heat-exchanged cores in future aero engine designs are explored and a discussion on the main drivers that could support such initiatives is presented. Finally, an intercooled core and conventional core turbofan engine optimisation procedure using TERA2020 is presented. A back-to-back comparison between the two engine configurations is performed and fuel optimal designs for 2020 are proposed.Whilst the detailed publications and the work carried out by the author, in a collaborative effort with other project partners, is presented in the main body of this thesis, it is important to note that this work is supported by 20 conference and journal papers.
|
|
| 7. |
- Kyprianidis, Konstantinos G., et al.
(författare)
-
Thermo-Fluid Modelling for Gas Turbines-Part I: Theoretical Foundation and Uncertainty Analysis
- 2009
-
Ingår i: ASME TURBO EXPO 2009 Proceedings, GT2009-60092.
-
Konferensbidrag (refereegranskat)abstract
- In this two-part publication, various aspects of thermo-fluidmodelling for gas turbines are described and their impact onperformance calculations and emissions predictions at aircraftsystem level is assessed. Accurate and reliable fluid modellingis essential for any gas turbine performance simulation softwareas it provides a robust foundation for building advanced multidisciplinarymodelling capabilities. Caloric properties forgeneric and semi-generic gas turbine performance simulationcodes can be calculated at various levels of fidelity; selection ofthe fidelity level is dependent upon the objectives of thesimulation and execution time constraints. However, rigorousfluid modelling may not necessarily improve performancesimulation accuracy unless all modelling assumptions andsources of uncertainty are aligned to the same level. Certainmodelling aspects such as the introduction of chemical kinetics,and dissociation effects, may reduce computational speed andthis is of significant importance for radical space explorationand novel propulsion cycle assessment.This paper describes and compares fluid models, based ondifferent levels of fidelity, which have been developed for anindustry standard gas turbine performance simulation code and an environmental assessment tool for novel propulsion cycles.The latter comprises the following modules: engineperformance, aircraft performance, emissions prediction, andenvironmental impact. The work presented aims to fill thecurrent literature gap by: (i) investigating the commonassumptions made in thermo-fluid modelling for gas turbinesand their effect on caloric properties and (ii) assessing theimpact of uncertainties on performance calculations andemissions predictions at aircraft system level.In Part I of this two-part publication, a comprehensiveanalysis of thermo-fluid modelling for gas turbines is presentedand the fluid models developed are discussed in detail.Common technical models, used for calculating caloricproperties, are compared while typical assumptions made influid modelling, and the uncertainties induced, are examined.Several analyses, which demonstrate the effects of composition,temperature and pressure on caloric properties of workingmediums for gas turbines, are presented. The working mediumsexamined include dry air and combustion products for variousfuels and H/C ratios. The errors induced by ignoringdissociation effects are also discussed.
|
|
| 8. |
- Kyprianidis, Konstantinos G., et al.
(författare)
-
Thermo-Fluid Modelling for Gas Turbines-Part II : Impact on Performance Calculations and Emissions Predictions at Aircraft System Level
- 2009
-
Ingår i: ASME TURBO EXPO 2009 Proceedings, GT-2009-60101. ; , s. 483-494
-
Konferensbidrag (refereegranskat)abstract
- In this two-part publication, various aspects of thermo-fluidmodelling for gas turbines are described and their impact onperformance calculations and emissions predictions at aircraftsystem level is assessed. Accurate and reliable fluid modellingis essential for any gas turbine performance simulation softwareas it provides a robust foundation for building advanced multidisciplinarymodelling capabilities. Caloric properties forgeneric and semi-generic gas turbine performance simulationcodes can be calculated at various levels of fidelity; selection ofthe fidelity level is dependent upon the objectives of thesimulation and execution time constraints. However, rigorousfluid modelling may not necessarily improve performancesimulation accuracy unless all modelling assumptions andsources of uncertainty are aligned to the same level. Certainmodelling aspects such as the introduction of chemical kinetics,and dissociation effects, may reduce computational speed andthis is of significant importance for radical space explorationand novel propulsion cycle assessment.This paper describes and compares fluid models, based ondifferent levels of fidelity, which have been developed for anindustry standard gas turbine performance simulation code and an environmental assessment tool for novel propulsion cycles.The latter comprises the following modules: engineperformance, aircraft performance, emissions prediction, andenvironmental impact. The work presented aims to fill thecurrent literature gap by: (i) investigating the commonassumptions made in thermo-fluid modelling for gas turbinesand their effect on caloric properties and (ii) assessing theimpact of uncertainties on performance calculations andemissions predictions at aircraft system level.In Part II of this two-part publication, the uncertaintyinduced in performance calculations by common technicalmodels, used for calculating caloric properties, is discussed atengine level. The errors induced by ignoring dissociation areexamined at 3 different levels: i) component level, ii) enginelevel, and iii) aircraft system level. Essentially, an attempt ismade to shed light on the trade-off between improving theaccuracy of a fluid model and the accuracy of a multidisciplinarysimulation at aircraft system level, againstcomputational time penalties. The results obtained demonstratethat accurate modelling of the working fluid is not alwaysessential; the accuracy/uncertainty for an overall engine modelwill always be better than the mean accuracy/uncertainty of the individual component estimates as long as systematic errors arecarefully examined and reduced to acceptable levels to ensureerror propagation does not cause significant discrepancies.Computational time penalties induced by improving theaccuracy of the fluid model as well as the validity of the idealgas assumption for future turbofan engines and novelpropulsion cycles are discussed.
|
|
| 9. |
- Kyprianidis, Konstantinos, et al.
(författare)
-
Low pressure system component advancements and its impact on future turbofan engine emissions
- 2009
-
Ingår i: XIX International Symposium on Air Breathing Engines (ISABE).
-
Konferensbidrag (refereegranskat)abstract
- Within the European research project EnVIronmenTALly Friendly Aero Engines, VITAL, a number of low pressure system component technologies are being investigated. The emerging progress will allow the design of new power plants capable of providing a step change in engine fuel burn and noise. As part of the VITAL project a Technoeconomic, Environmental and Risk Assessment tool, the TERA2020, is being developed. Within this tool, means to assess the impact of component technology progress on the engine/aircraft system level has been implemented. Sensitivities relating parameters traditionally used to describe component performance, such as allowable shaft torque, low pressure turbine stage loading, fan blade weight and system level parameters have previously been published. The current paper makes an assessment of the impact of failing to deliver specific technology advancements, as researched under the VITAL project. The impact has been quantified, in terms of power plant noise and CO2 emissions.
|
|
| 10. |
- Kyprianidis, Konstantinos, et al.
(författare)
-
The TERA Approach - A Methodology for Technoeconomical, Environmental and Risk Analysis of Multidisciplinary Systems
- 2008
-
Konferensbidrag (refereegranskat)abstract
- This paper presents a methodology for Technoeconomical, Environmental and Risk Analysis (TERA) of multidisciplinary systems. Work in Cranfield University on the development and adaptation of TERA models for complex mechanical systems can be traced back to the early 90’s. Tools implementing the “TERA approach” can be used for radically exploring the design space available in novel aero engine configurations during the conceptual design phase. The methodology can be used for assessing advanced power generation schemes and for technology risk analysis. Details of the application of the method in aero engine design and industrial power generation systems are given together with sample results. TERA can rank and make a selection among different power generation cycles, for various objectives, so that investments can be allocated efficiently. The capability of the tool to identify those gaseous pollutants and flight phases that contribute the most to global warming is illustrated.
|
|
