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To inform you of the different types of gas turbine engines; their applications, on-design, off-design and transient performance.

To provide you with the ability to undertake gas turbine component performance calculations, diagnostics and to perform evaluations of gas turbine performance, and deterioration.

Gas Turbine Types and Applications

Effect of design parameters such as pressure ratio and turbine temperature on the basic gas turbine cycle. Modifications of the basic Brayton cycle, compounding, intercooling, reheating, heat exchange, bypass, and fan cycles. Simulation of the above.

Performance and Simulation

Design point performance of turbojet, turbofan and turboshaft cycles, effect of bypass ratio. Off design performance, effect of ambient temperature, altitude, throttle setting and flight speed. Non-dimensional representation. Gas turbine simulation. Effects of bleeds and power offtakes. Compressor turbine matching. Gas turbine degradation. Simulation and diagnostics of the above. Component maps. Surge alleviation, performance improvements, steady-state, and transient performance. Off-design performance calculations and iteration techniques Accelerations, decelerations, effects on surge margin. Transients of single shaft and multi-shaft engines. Transient performance simulation. Effects of heat transfer on transient performance.

Software used for gas turbine performance simulation: TURBOMATCH

Diagnostics and Monitoring.

Description of gas turbine performance degradation and faults.

Description of most used gas turbine condition monitoring techniques.

Software used for diagnostics: PYTHIA

On successful completion of this module you should be able to:

1. Examine gas turbine components and critically evaluate their performance in terms of power, thrust and specific fuel consumption, for state-of-the-art as well as future technology trends, of various types of gas turbine engines.
2. Analyse the results from quantitative evaluations of gas turbine designs, formulated based on first principles, and use engineering judgement to determine appropriate power or propulsion systems for different applications.
3. Set up numerical iterative methods for the matching of engine components to generate whole engine performance models that resemble actual engine operations.
4. Assess the impact of different degradation mechanisms and faults on gas turbine performance, including considerations of engine life cycle and maintenance intervals.
5. Assemble computer-based simulation and diagnostic analysis models to simulate engine performance and detect its faults, using current state-of-the-art methods from literature and critically evaluating the methods' validity and limitations.

To familiarise you with the common problems associated with the mechanical design and the lifting of the major rotating components of the gas turbine engine.

Loads/forces/stresses in gas turbine engines: The origin of loads/forces/stresses in a gas turbine engine such as loads associated with: rotational inertia, flight, precession of shafts, pressure gradient, torsion, seizure, blade release, engine mountings within the airframe and bearings. Discussion of major loadings associated with the rotating components and those within the pressure casing including components subject to heating.

Failure criteria: Monotonic failure criteria: proof, ultimate strength of materials. Theories of failure applied to bi-axial loads. Other failure mechanisms associated with gas turbine engines including creep and fatigue. Fatigue properties including SN and RM diagrams, the effect of stress concentration, mean stress etc. Cumulative fatigue, the double Goodman diagram technique to calculate the fatigue safety factor of gas turbine components. Methods of calculating the creep life of a component using the Larson-Miller Time-Temperature parameter.

Applications: The design of discs and blades. Illustration of the magnitude of stresses in conventional axial flow blades by means of a simple desk-top method to include the effects of leaning the blade. The stressing of axial flow discs by means of a discretised hand calculation which illustrates the distribution and relative magnitude of the working stresses within a disc. The design of flanges and bolted structures. Leakage through a flanged joint and failure from fatigue.

Blade vibration: Resonances. Desk top techniques for calculating the low order natural frequencies of turbomachine blades. Allowances for the effects of blade twist and centrifugal stiffening. Sources of blade excitation including stationary flow disturbance, rotating stall and flutter. Derivation of the Campbell diagram from which troublesome resonances may be identified. Allowances for temperature, pre-twist and centrifugal stiffening. Methods for dealing with resonances.

Damage Mechanisms and Lifing: Fundamentals of Creep and Fatigue damage mechanisms. Material, design and operational parameters that affect creep and fatigue. Experimental and test procedures to characterise creep and fatigue damage. Classification of Fatigue-Low Cycle and High Cycle and use of appropriate methods: Strain Vs Stress Methods. Cumulative damage assessment using cycling counting and linear damage rules -Milner Approach.  

On successful completion of this module you should be able to:

1. 1. Describe and distinguish the design requirements and loads encountered by gas turbine components during normal operation.
2. 2. Evaluate and assess the loads, stresses, failure criteria and factors of safety used in gas turbine engines.
3. 3. Evaluate impact of vibrations on design and operation of gas turbine.
4. 4. Assess the creep and fatigue damage of gas turbine components based on design and operational parameters.

To familiarise you with compressor and turbine aerodynamic design and performance by instruction, investigation and example.

To introduce you to the technology of gas turbine blade cooling through analytical and practical approaches of heat transfer principles, convection cooling, impingement film transpiration cooling and liquid cooling.

Thermofluids: Introduction to aerodynamics, thermofluids, and compressible flows.

Compressor Design and Performance

Overall performance:  Fundamentals of axial flow compressors.  Overall performance, achievable pressure ratio and efficiency. The effect of Reynolds number, Mach number, and incidence. Definition of isentropic and polytropic efficiency, effect of pressure ratio, performance at constant speed, surge and surge margin definitions, running line, choking effects.

The axial compressor stage: Stage loading and flow parameters, limitation in design on pitch line basis. Definition and choice of reaction at design, effect on stage efficiency. Loss sources in turbomachines and loss estimation methods. The ideal and real stage characteristic, stall and choke. The free vortex solution, limitations due to hub/tip ratio. Off-design performance Choice of overall annulus geometry, axial spacing, aspect ratio, limitations of rear hub/tip ratio. Compressor blading: selection of blade numbers, aspect ratio and basic blade profiling.

Compressor design example: Multi-stage compressor design example carried out for a HPC.

Turbine Design and Performance

Overall performance: the expansion process and characteristics, annulus layout and design choices, choice of stage loading and flow coefficient, engine overall performance requirements, overall annulus geometry and layout; rising line, constant mean diameter and falling line.

The axial turbine stage: Aerodynamic concepts and parameters, velocity triangles, reaction, stage loading, flow coefficients. The ideal and real characteristic. Design  for maximum power: effect of choking and change of inlet temperature and pressure.  Stage efficiency, overtip leakage, profile losses, correlations. Three-dimensional design aspects. Radial equilibrium and secondary flows.

Turbine blading: choice of base profile, blade numbers and aspect ratio. Zweiffel's and alternative lift coefficients.

Turbine Design Example: An aerodynamic design example is carried out for a HPT Heat Transfer Principles: Brief review of heat transfer principles and physical significance of non-dimensional groupings. Conditions around blades, boundary layers, external heat transfer coefficient distribution, effect of turbulence. Root cooled blades and NGVs, analytical and numerical methods of determining spanwise temperature distribution. Fibre strengthened and nickel base alloys.

Need for high turbine entry temperature: effect on engine performance.

Development of materials, manufacturing processes and cooling systems.

Convection Cooling: Convectively cooled aerofoils: analytical approach for metal and cooling air spanwise temperature distribution. Cooling passage geometry and heat transfer characteristics. Cooling efficiency, cooling effectiveness and mass flow function: application at project design stage for determining metal and cooling air temperatures. Methods for optimising cooling system design: secondary surfaces and multipass. Internal temperature distribution of cooled aerofoils: calculations, comparisons with experimental results.

Impingement, Film and Transpiration Cooling: Principles steady state and transient performance, characteristics, advantages, limitations, comparison with convection cooling. Cooling air feed and discharge systems. Integration of cooled turbine with aerodynamic performance and main engine design. Co-ordination of design responsibilities. Example of cooled turbine stage design.

Liquid Cooling: Liquid cooling: principles, advantages and limitations, practical examples.

On successful completion of this module you should be able to:

1. 1. Identify and analyse the design and performance characteristics of turbomachinery components.
2. 2. For given inlet conditions and requirements, determine the aerodynamic performance characteristics of a turbomachine and comment on the feasibility of the design.
3. 3. Differentiate the key design choices for axial compressors and turbines, Construct an assessment of the aspects which affect the design and performance of axial turbomachines an apply formulations and critical evaluations of underpinning turbo-machinery theories.
4. 4. Explain the requirement for ethical and professional conduct in the use of data and in the presentation of results and calculations.
5. 5. Explain the major differences between the various heat transfer and cooling architectures and apply the concepts and theories of heat transfer and different cooling technologies to the cooling of turbine blades to produce a realistic assessment of their cooling requirements.

To make you familiar with design, operation, computation and performance criteria of gas turbine (GT) combustion and reheat systems and to explore issues related to gas turbine pollutant emissions.

Introduction to GT combustor design considerations and sizing methodologies:

Diffusion and pre-mixed flame characteristics; GT combustor design features and performance requirements; Design considerations and main functions of the primary, intermediate and dilution zones; Fundamental aspects of the ignition process; Sources of pressure loss; Performance criteria and requirements for pre-combustor diffusers; Faired and dump diffusers; Combustor sizing methodologies based on the pressure loss approach, combustor efficiency requirements and altitude relight requirements.

Combustion efficiency:

Definition of combustion efficiency and combustion efficiency requirements; Evaporation rate controlled systems – influence of fuel type, turbulence and pressure, drop size and residence time; Mixing rate controlled systems; Reaction rate controlled systems – derivation and significance of the theta parameter.

Overview of GT generated pollutants:

Products of combustion and their consequences; Mechanisms of formation of GT pollutants; Effects on the environment and/or human health; Overview of limitation strategies and associated challenges; Low emissions combustion systems for aero and stationary gas turbines; Emissions legislation and targets.

GT combustor heat transfer and cooling:

Combustor buckling and cracking; Need for efficient methods of liner cooling; Heat transfer processes (Internal and external radiation, internal and external convection, conduction); Calculation of uncooled liner temperature; Effect of chamber variables on heat transfer terms, liner wall temperature and liner life; Film cooling techniques; Advanced wall cooling techniques; Combustor liner materials and thermal barrier coatings.

GT fuels

Appraise types and properties of fuels; Methodologies to calculate combustion temperatures for various fuel types, mixture strengths and pressures (both non-dissociated and dissociated).

Computational methods for GT Combustors

Role of CFD in combustor design and development; Application of CFD for preliminary design, prognostics and diagnostics of combustion systems.

Introduction to GT afterburners:

Requirement and principle of afterburning; Effects of afterburning on engine performance; General arrangement, main components and design features of afterburners; Ignition methods for GT afterburners; Control requirements and methods for engines with afterburners; Considerations for selection of convergent and convergent-divergent nozzles.

On successful competition of this module you should be able to:

1. Explain, evaluate and apply engineering principles underpinning the design of gas turbine combustors and reheat systems for both aero and stationary gas turbines, and explain the influence of the design choices on overall engine configuration, performance and emissions.
2. Assess the influence and necessary trade-offs of combustor performance, efficiency, durability, emissions legislation and operational requirements on combustor diffuser and liner aerodynamic design, fuel injector and fuel spray characteristics, fuel staging, liner cooling and material technologies.
3. Apply heat transfer engineering principles to the calculation of combustor liner temperature and assess the effect of engine operating conditions, materials, advanced cooling methods and thermal barrier coatings on the life of a combustor liner.
4. Employ stoichiometry methodologies to calculate combustion temperatures and combustion products for various fuel types, fuel to air ratios, and combustor inlet temperatures and pressures.
5. Distinguish between reduced order models and higher fidelity computational methods for combustor performance and emissions prediction, demonstrating engagement with established technical knowledge and literature, and critically evaluating their modelling capabilities, robustness and limitations.

To familiarise you with engine systems or engine designs for stationary and aero gas turbines and technical reporting by examples and sources systematic analysis.

Assessments of engine systems, auxiliaries, families of engines, and/or engine and component designs for both aero and stationary gas turbines are addressed by means of a 'Systems Symposium', run by the MSc class.

Topics covered by the systems symposium include: intake systems for aero engines and industrial gas turbines; anti-icing systems for aeroengines and industrial gas turbines; start systems for aeroengines and industrial gas turbines; start sequences for industrial gas turbines; compressor bleed and variable guide vanes; variable geometry nozzle guide vanes; gas path sealing of aero gas turbines; noise control of gas turbines; air filtration for industrial gas turbines; compressor and turbine cleaning systems; full authority and other electronic control systems; key gas turbine component design technologies, etc.

Topics may also cover design technologies of gas turbine engines and their components, different families of engine products of major gas turbine manufacturers in different countries, comparison of competitive engines, etc. The objective is to undertake an evaluation of a specified aspect of gas turbine engineering, to make a presentation and to provide a technical review paper or design and assessment on a particular subject. 

Another aspect of the module is that the presentations are made in a conference format which requires you to work together to plan, organise and execute the events.

Outline syllabus for a few sample individual topics:

• Ignition system: Requirements and problems of altitude relight.  Types of system -booster coils, high frequency, high energy and their applications.
• Starting Systems: Electrical systems - low and high voltage, turbine systems- cartridge, iso-propyl nitrate, fuel-air, gas turbine, low pressure air and hydraulic systems and their applications.
• Air systems: requirements, methods of cooling, pressure balancing of end loads, sealing, and applications.
• Preliminary design of axial high pressure compressor: requirements, design criteria, preliminary design, analysis of design results, etc.

On successful completion of this module you should be able to:

1. Compose a structured technical report in the form of a conference paper, critically evaluating established technical literature and data to substantiate arguments and conclusions.
2. Conduct a systematic analysis of a range of sources to identify, critically analyse and assess the main technologies of a key aspect of gas turbine engineering, including their environmental and societal impacts.
3. Report and defend the technical outcomes of the systematic analysis in the form of a conference paper and presentation, demonstrating communication skills to technical and non-technical audiences.
4. Work effectively with others in groups to deliver a Gas Turbine Systems Symposium based on a scientific conference.
5. Collaborate in different capacities to formulate a business/management plan to market and communicate the Engine Systems Symposium to the wider gas turbine community for encouraging the attendance of external agencies.

The importance of technology leadership in driving the technical aspects of an organisation’s products, innovation, programmes, operations and strategy is paramount, especially in today’s turbulent commercial environment with its unprecedented pace of technological development. Demand for ever more complex products and services has become the norm.

The challenge for today’s manager is to deal with uncertainty, to allow technological innovation and change to flourish but also to remain within planned parameters of performance. Many organisations engaged with technological innovation struggle to find engineers with the right skills.

Specifically, engineers have extensive subject/discipline knowledge but may benefit from developing a deeper understanding of management processes in an organisational context.  

• Engineers and Technologists in organisations: The role of organisations and the challenges facing engineers and technologies.
• People management: Understanding you. Understanding other people. Working in teams. Dealing with conflicts.
• The Business Environment: Understanding the business environment; identifying key trends and their implications for the organisation.
• Strategy and Marketing: Developing effective strategies; Focusing on the customer; building competitive advantage; The role of strategic assets.
• Finance: Profit and loss accounts. Balance sheets. Cash flow forecasting. Project appraisal.
• New product development: Commercialising technology. Market drivers. Time to market. Focusing technology. Concerns.
• Business game: Working in teams (companies), students will set up and run a technology company and make decisions on investment, R&D funding, operations, marketing and sales strategy.
• Negotiation: Preparation for Negotiations. Negotiation process. Win-Win solutions.
• Presentation skills: Understanding your audience. Focusing your message. Successful presentations. Getting your message across.

On successful completion of this module you should be able to:

1. 1. Recognise the importance of teamwork in the performance and success of organisations with particular reference to commercialising technological innovation.
2. 2. Operate as an effective team member, recognising the contribution of individuals within the team, and capable of developing team working skills in themselves and others to improve the overall performance of a team.
3. 3. Compare and evaluate the impact of the key functional areas (strategy, marketing and finance) on the commercial performance of an organisation, relevant to the manufacture of a product or provision of a technical service.
4. 4. Design and deliver an effective presentation that justifies and supports any decisions or recommendations made.
5. 5. Argue and defend their judgements through constructive communication and negotiating skills.

To familiarise you with various operations of gas turbines and other driven rotating machines.

Gas Turbine Operations:

• An overview of the different operational regimes for gas turbine application. This explores base load, peak load, standby and backup operations, alongside their individual operational requirements. It also includes engine control modes such as operating at approximately constant exhaust gas temperature and load-following mode. Analysis of gas turbine performance and health using machine sensor data from actual operation is also a key part. This part also highlights the use and impact of ancillary equipment (air filtration and compressor washing systems) in improving the performance and extending the operating hours of gas turbine machines. Gas turbine operational flexibility for back-up of renewable power.

Steam Turbine Operations:

• Steam turbine fundamentals, applications and selection. This includes an overview of steam turbine plants operating on fossil fuel - combined cycle gas turbines (CCGT) and combined heat and power (CHP) operations. It also covers aspects of heat recovery systems, condensers, pumps and other auxiliary equipment.

Diesel Engines for Heat and Power:

• Diesel engine fundamentals; theory and principles. This includes 2-stroke (crosshead engine) and 4-stroke (trunk piston) types, their installation and operations. Utilisation of diesel engine waste heat recovery for district heating hot water systems, cooling systems using chiller and fresh water generation are the common applications explored. Diesel engine fuels and the means of controlling exhaust emissions are included.

On successful completion of this module you should be able to:

1. Evaluate gas turbine performance using machine data from actual operations, using appropriate analytical methods.
2. Assess engine performance deterioration and propose improved approaches for performance enhancement using evidence-based case studies.
3. Critically compare design key components and parameters and relate them to steam turbine theory, performance/operation.
4. Differentiate and assess the design/applications and efficiency of steam turbines, supported by technical literature.
5. Calculate diesel engine performance, differentiate 2- and 4-stroke engines and the operational requirements, for heat and power.

You must submit a design or research thesis. This may be delivered through collaboration with an industrial sponsor or driven by the research interests of the Thermal Power MSc academic team. The thesis should set out the results of a structured programme of work and demonstrate your ability to conduct focused investigations, to test ideas (your own or those of others) and to obtain appropriate conclusions.

The results of the research programme should be set in the context of related work previously produced by others. You are required to communicate your findings in a thesis written in the style of a detailed document describing previous work, methods employed, results, conclusions, and recommendations. You should explain, discuss and evaluate the ethical, environmental, economic and social implications of the results and findings. The Thesis must be an independent, detailed, self-standing document, describing to potential industrial sponsors the context, value, and outcomes of the work.

On successful completion of this module, you should be able to:

1. Acquire, analyse and synthesise technical literature and data from computation or experiment, and use it to evaluate a research/design question within a gas turbine or related area.
2. Formulate clearly defined project objectives and use them to critically select, justify, and apply appropriate methodologies to design or operational solutions that address the objectives.
3. Plan and execute an extensive work programme, culminating in the production of a thesis incorporating analysis, discussion of results and conclusions in a thesis.
4. Critically evaluate the potential environmental or societal impacts of the research or design outcomes, considering sustainability, regulatory context, or responsible engineering practice.
5. Synthesise and present the findings of the project in the context of existing research and practice and communicate them effectively through a professional poster presentation to technical and non-technical audiences.

To introduce you to computationally-based flow modelling, applicable to turbomachinery components and gas turbine engines.

To introduce you to the theoretical background of Computational Fluid Dynamics and to the limitations of CFD when applied to the solution of turbomachinery fluid flow problems. To provide experience in the use of a commercial CFD code through planning and conducting investigations of complex turbomachinery flow cases.

Flow Modelling Strategies
Introduction to computational fluid dynamics and the role of CFD in engine component evaluation and improved design. Review of current capabilities and future directions.

Physical Modelling
Governing Navier-Stokes equations. Approximate forms. Turbulence - turbulent averaging, mathematical closure and turbulence modelling. Scalar transport and chemical reaction. Reynolds averaging, Large Eddy Simulation, Direct Numerical Simulation.

Finite Difference Equations
Problem classification. Discretisation. Solution methods. Pressure correction. Boundary conditions. Mesh generation for practical flow geometries.

Practical Demonstration
Introduction to commercially available general purpose CFD codes (FLUENT and CFX). Case study tutorials and assessed assignment.

On successful completion of this module a you should be able to:

1. 1. Summarise the key steps associated with the CFD modelling approach whilst adhering to good practice in the employment of numerical tools.
2. 2. Design effective turbomachinery grid generation strategies to ensure numerical models are successfully employed.
3. 3. Describe the fundamentals of turbulence modelling when applied to turbomachinery flows.
4. 4. Plan, conduct, analyse and evaluate an engineering fluid problem using a commercial CFD package (Ansys Fluent/CFX).
5. 5. Use CFD tools to generate effective analyses, evaluations and reporting of turbomachinery flow simulations.

To provide you with an understanding of the design and performance of aviation propulsion systems for fixed-wing, rotary-wing and UAV applications.

• Gas turbine fundamentals Basic principles; thermodynamics; gas dynamics; dimensional analysis; ideal (Joule) gas turbine cycle,
• Gas turbine components Fixed-wing intakes; rotary-wing intakes; centrifugal-flow compressors; axial-flow compressors; combustion chambers; axial-flow turbines; nozzles,
• Aviation internal combustion engines Petrol engine (Carnot) cycle and applications, diesel engine cycle and application,
• Applications Aircraft propulsion; turboshaft cycle; turbojet cycle; turbofan cycle; the engine running line. STOVL aircraft applications. IC engine applications.

On successful completion of this module you will be able to:

• Explain the principles of propulsion system design and operation,
• Relate the design of propulsion system components to the overall system performance,
• Evaluate the performance of various types of propulsion units fitted to modern classes of aircraft.

To familiarise you with various marine propulsion technologies, propulsion auxiliary and their integration

The module will be covered in the following four parts:

1. Ship Propulsion Systems
   • An overview of Gas Turbine, Diesel, Steam propulsion systems and their combination. This will include evaluating their advantages/disadvantages, optimal performance of various configurations, performance analysis and integration.
• An overview of hybrid and electric technology for ship propulsion and their relative merits and demerits.
2. Ships Auxiliary systems
   • Introduction to ship design concepts, fundamentals of ship resistance, control surfaces, boundary layers and propulsion coefficients.
   • Overview of propulsion train which includes different types of propellers, shafting, ‘A’ Brackets, gearbox and other components.
   • Understanding principles of hull vibration, propeller cavitation, shaft torsional vibration and their effect on the propulsion system performance.
3. Propulsion System Integration
   • This part focuses on understanding the integration of propulsion system which includes the prime-movers, auxiliaries, and other associated systems/ control mechanism.
   • Introduction to ³ÉÈËÖ±²¥’s Poseidon+ simulation for propulsion system integration.
4. Alternative fuels and Regulatory framework
   • An overview of predicted future energy trends/sources, alternative fuels for marine usage (natural gas, di-methyl ether, hydrogen, ammonia, nuclear options, photo-voltaic, etc..) in the light of decarbonisation in the maritime sector.
   • Introduction to emissions, MARPOL, SOLAS, Flag & Port state, marine safety issues etc.

On successful completion of this module you should be able to:

1. 1. Compare different marine propulsions technologies, evaluate their performance, and specify parameters for selecting a suitable propulsion system.
2. 2. Distinguish between various ship auxiliaries, their performance and examine suitability for a given propulsion system.
3. 3. Evaluate the performance of a given propulsion system as a whole and highlight integration issues.
4. 4. Compare different types of fuels/energy sources for a given propulsion system and analyse its compliance with the prevailing regulatory and safety framework.
5. 5. Assess Techno-Economic parameters and sustainability of the selected propulsion system.