Tutorial of Basics

Hot and high performance is key for helicopters and hence the engine cycle design strategy needs careful consideration. This two-hour tutorial session will provide an introduction to engine cycle design and optimization process, whilst overviewing the key drivers behind cycle selection. In the session, firstly the helicopter requirements (missions and point performance), military versus civil or dual usage issues, together with one engine versus two engine considerations will be discussed, different engine architectures will be looked at. Secondly, the session will introduce the engine rating structure and the limits, whilst walking through the steps of cycle design and optimization process. Finally, the major key drivers like growth potential, family concept, derivative engine strategies and future vertical lift - fast rotorcraft concepts will be presented. This tutorial of basics is perfect for anyone new to helicopter engine or wishing to expand their basic knowledge in this area.

Key learning objectives:

1. Identify different types of helicopter platforms and their missions.
2. Explain the rating structure.
3. Address different types and architectures of turboshaft engines.
4. Identify the engine cycle selection criteria.
5. Explain how the engine limits are defined.
6. Explain how the growth potential and family concept affect the cycle design.

Gas Turbines market, especially for the applications in Oil & Gas and Power Generation, is demanding rising sustainability requirements. Manufacturers are therefore required to implement actions and policies to continue playing a strategic role for the global goals of sustainable development and reduction of global warming. The application of environmental life-cycle assessment from the early stages of product design is becoming a critical driver to develop a competitive product also from an environmental perspective. As a matter of fact, the earlier application of design-for-environment techniques can effectively influence the decisions towards a comprehensive sustainability:

What is Life Cycle Assessment?

• LCA methodology with reference to available ISO standards (ISO 14040, ISO 14044, ISO 14067)
• Goal and scope, functional unit, and system boundaries
• Inventory phase, attributional vs consequential LCA
• Impact assessment, impact categories, end point vs mid point
• Interpretation, single score, product category rules
• Applications for the Oil & Gas sector, specifically on Gas Turbines
• Case study on the application of LCA during a new product development at Baker Hughes
• Potentiality to reduce the environmental impact during the design phase
• Conclusions

Aero and Industrial Gas turbines with low specific fuel consumption and reduced CO2 emissions require high combustor outlet temperatures with a continued emphasis on reducing emissions, without sacrificing operability or durability. In addition, Combustion systems are increasingly expected to operate with synthetic gaseous fuels or alternative liquid fuels. The Combustion, Fuels & Emissions sessions will highlight new technology and design approaches, using both experimental and computational techniques, employed to achieve improved combustor performance including ultra-low pollutant emissions and enhanced operability such as turndown and transient response. Broad trends for the 2017 conference include a continued focus on combustion dynamics for lean-staged combustion systems, significant innovation in the development of combustion system such as Dry Low NOx or novel rotary detonation, maturation of large eddy simulation analyses, as well as continued research of fundamental and applied topics in automation, mixing, ignition, autoignition, blowout and chemical kinetics.

The Cycle Innovations Committee is dedicated to the advancement of technology and innovation, with a particular focus on the thermodynamic cycles of gas turbine–based plants for power generation and propulsion. Special attention is also devoted to energy storage technology and management aspects. The Committee traditionally attracts paper submissions from a wide range of disciplines and scientific areas.

Some of the thematic areas the Committee currently encompasses are listed below:

• Low or no emissions thermal cycles and advanced CO2 handling
• Supercritical CO2 cycles
• H2 production and utilization
• Polygeneration cycles and process integration (power, heat, cooling, fuels, chemicals)
• Advanced steam and humid air cycles
• Steam and water injection gas turbine cycles
• Closed cycle gas turbine technology
• Novel aero propulsion systems for aircraft and rotorcraft
• Novel marine propulsion systems
• Innovative heat recovery steam generators & once through steam generators
• Renewable and bio-energy concepts and innovative cycles
• Concentrated Solar Power systems incorporating gas turbine technology
• Fuel cell driven cycles and hybrid systems
• Externally fired gas turbines and high temperature heat exchangers
• New cycles for distributed power generation
• Thermo-economic and environmental impact analysis
• Cycle simulation and analysis for performance and health assessment
• Low temperature heat recovery cycles
• Geothermal cycles
• Innovative control systems for power plants
• Optimization of traditional and innovative energy and propulsion systems
• Electrical energy storage
• Thermal energy storage (hot water, phase changing materials, nanomaterials, thermochemical devices, etc.)
• Storage solutions for hydrogen or complex chemicals
• Compressed air energy storage

With continuing interest in clean energy and energy storage through the production and use of Hydrogen (H2), there is a growing need to fully understand the impact of H2 on existing infrastructure while also looking into the development of new technologies for future demand. This tutorial will take a detailed look into H2 applications and the challenges that it presents, whether it is the use of pure H2 or blending hydrogen with natural gas in existing pipeline infrastructure. Various applications that will be looked at are Propulsion, Petrochemical, and Energy Storage. In addition, this tutorial go over methods of H2 production and H2 compression to look at how the H2 is created and how it is injected into pipelines, fuel cells, and other forms of storage. In terms of compression, H2 presents many challenges due to its low molecular weight and high head rise to pressure ratios. It is important to look into existing technologies that are used for current hydrogen production but also understand their limits and capabilities while also looking into novel designs as demand continues to increase. After compression, there is a need to look into various methods for storing hydrogen, whether it is through liquid which will require more cooling, high pressure gas, carriers, sorbents, and additional options. Another challenge with H2, is its effect on materials typically used in pipeline systems. Due to its molecular size, hydrogen embrittlement at higher pressures is a serious concern as it could potentially weaken high pressure storage vessels and pipelines and lead to premature failure. This leads to a need to understand what materials are most effective with high concentrations of H2 while also understanding the impact on existing materials. This leads to a detailed breakdown of the potential for hydrogen blending and what concentrations are acceptable without compromising existing infrastructure to reduce cost and lead time for injecting more H2 into the pipelines. Lastly, the tutorial will look at H2 impacts on combustion by diving into combustion fundamentals, capabilities with current technologies, and novel designs that can improve performance with H2.

Grid-scale energy storage is needed to enable deep penetration of renewable power generators like solar photovoltaic and wind farms into the energy mix. The minute-by-minute, hourly, and seasonal variability associated with these renewable resources is poorly matched with power usage. Conventional power generation from fossil fuels or nuclear sources is typically required in order to provide sufficient power quality and reliability, although this approach results in operational profiles that require significant ramp rates and turndown, reducing the efficiency and life of conventional plants. Grid-scale energy storage systems would absorb power from the grid during periods of excess renewable generation, and release the stored energy to generate power when renewable sources are unavailable. Lithium-ion or other battery chemistries are being introduced as a potential solution, but all existing technologies are currently cost-prohibitive at the many Megawatt- or Gigawatt-scales for more than about 2-4 hours.

There are many existing or developing machinery-based energy storage systems to fulfill this need, including pumped hydro, flywheels, compressed air, gravitational, liquid air, pumped thermal (example images below), and various thermochemical technologies such as hydrogen, ammonia, synthetic natural gas, sulfur, and other "Power-to-X" technologies.

This tutorial reviews all of these technologies including basic working principles, role of turbomachinery, hybridization with existing power generators, state of development, advantages and disadvantages relative to other technologies, and research & development needs for system improvements and commercialization.

Improvements in fans and blowers are means to address the global energy challenge, with manufacturers increasingly focusing on improvement in fan efficiency under legislative pressure and as a part of their response to global climate change.

The academia-industry collaboration and the up-front use of Computational Fluid Dynamics (CFD) and Experimental Fluid Dynamics (EFD) are the key ingredients to facilitate the advancement from traditional empirical design methodologies. In response to these challenges, the ASME-IGTI Fans and Blowers Technical Committee consider all technical aspects associated with fans and blowers, with a special emphasis on:

• Design and optimization
• CFD methods for unsteady aerodynamics
• Noise generation, prediction, innovative noise reduction design
• Psycho-acoustic and noise perception in installations
• Structural mechanical aspects (vibration, fatigue and flutter)
• Emerging technologies in flow and noise control
• Operations and system effects and interactions
• Maintenance, repair & life time management
• Standards, compliance with legislation & regulations
• Evaluation of education curricula for fan technology and systems

The tutorial is of interest for all engineers concerned with understanding and improving the performance and durability of turbine passages utilized in aviation and power generation industry.

The tutorial is aimed at providing an overview of the research work conducted to understand the loss generation mechanisms in the turbine passages with particular focus on basic experiments investigating the impact of inlet boundary layer profile in two- and three-dimensional airfoils in linear and annular cascades operating at design incidence angles over a range of Reynolds numbers and Mach numbers. The experimental data includes static pressure and heat load distribution on airfoil and end-wall surfaces, evolution of losses in the cascade passages, flow visualization studies in water tunnels and surface streak-lines. Limited number of experimental data is also shown highlighting the impact of flow unsteadiness induced by upstream airfoil passages on the secondary flow. Attempts to reduce secondary flow losses using three-dimensional airfoil and end-wall contouring are also discussed. Although several very promising loss reduction concepts have been developed and implemented to improve the design of turbine passages, the tutor believes there is still an opportunity to further enhance the performance of turbines by developing deeper insight in the loss generation mechanisms. Both basic experimental programs and higher fidelity numerical simulations will be required to achieve this goal.

Through collaborative research, testing and deployment over the last 40 years, the gas turbine industry has successfully designed and built many new systems for cleaner, reliable energy and environmental objectives. Various types of small and large gas turbine units are used in a variety of pipeline compressor stations, simple and combined cycle power plants, as well as for cogeneration and district energy. They comprise the range from microturbines, aeroderivative units, and industrial frame units operating on a variety of liquid and gaseous fuels that deliver the hot high pressure airflow to produce power and heat output.

This tutorial takes a concise look at air pollution and greenhouse gas emissions from various types of gas turbine systems is presented. The presentation includes:

• How emissions are formed by high pressure fuel combustion in various types of gas turbine systems, with fuel flexibility, syngas and hydrogen considerations
• Cost-effective solutions for the prevention and control of NOx and carbon monoxide, including water and steam injection, Dry Low NOx combustion, and backend controls for NOx and CO2 emissions
• How policy and regulations can be developed to address air pollution, greenhouse gas emissions and system efficiency through output-based environmental standards to promote comprehensive solutions.

Gas turbine design and performance is constrained by the properties of the materials from which the hot section components have been manufactured. This tutorial covers three main areas of metallurgical and materials engineering activity; alloy design, manufacturing processes and material service behaviour. Application examples will be drawn from throughout the gas turbine industry.

1. Alloy Design and Basic Metallurgical Concepts - A review of basic metallurgical principles; alloys, phases, microstructure, strengthening mechanisms and environmental resistance with a specific focus on superalloys
2. etallurgical Processing I: Casting, forging, powder metallurgy and additive manufacturing; with examples from turbine component manufacture and repair.
3. Metallurgical Processing II: Coating; with examples from airfoil coating materials formed by diffusion and thermal-spray overlay processes.
4. Metallurgical Investigation: Service behavior, damage mechanisms and metallurgical analysis of turbine components

Key Learning Objectives

The tutorial is targeted to non-metallurgists whose exposure to metallurgy and materials may have been limited to a general introductory undergraduate metallurgy course. Attendees should come away with:

• An understanding of how superalloys develop their unique properties
• Familiarity with the processes used to manufacture turbine hot section components
• Basic understanding of the types of high temperature coatings, their function and how they are applied
• An appreciation for how turbine hot section materials may degrade due to operation in a turbine.

The selection of materials for various components of steam turbines and centrifugal compressors is a significant factor in the overall cost and delivery of the units. The mechanical properties of materials selected also heavily influence the mechanical design and efficiency of the unit, while the corrosion resistance and elevated temperature properties of the material can play a significant role in the expected service life. Industrial standards such as API 612 for steam turbines and API 617 for centrifugal compressors, along with ASME Boiler and Pressure Vessel Code, provide guidelines for commonly accepted materials for many critical components established through a proven service history. Other standards such as NACE MR0103 provide minimum requirements for avoiding stress corrosion cracking in the presence of Hydrogen Sulfide. This tutorial will review the major components of centrifugal compressors and steam turbines within the oil and gas industry, explaining why these materials are utilized in terms of mechanical properties under service conditions, commercial availability, fabrication techniques and corrosion resistance.

Due to the various aggressive corrosion and erosive environments in which both compressors and turbines can be operated in, coatings are sometimes used to prolong the service life. The various types of coatings that can be applied, along with their application methods, will be reviewed.

The Oil and Gas Industry is a large user of turbomachinery. The demand for oil and gas is consistently growing, and changing market conditions require innovative solutions. Operation and optimization of turbomachinery in a variety of Oil & Gas applications is therefore of great interest. Moreover, potentially extreme operation environments require the consideration of innovative design and operational attributes. Sessions in the Oil & Gas Applications Committee address both theoretical and practical Oil & Gas industry perspectives. The technical sessions provide the latest information on gas turbines and compressors in pipeline and compression stations. Particular emphasis is given to design, operation and maintenance, management, dynamic behavior, diagnostics and vibration and noise, as well as to all engineering issues in Oil & Gas applications.

Wet gas compression and multi-phase pumping are also addressed, due to the increasing interest in many installations. The Oil & Gas Applications Committee brings industry experts together in panel and tutorial sessions jointly held by both academic educators and industry professionals. Both basics of Oil & Gas installations and off-design operation issues will be covered, aimed to ensure improved efficiency and safe and reliable operation. The latest information about environmental impact, product upgrade, risk assessment, standards and legislation of gas turbines and compressors in Oil & Gas applications is also provided.

While power generation and aircraft applications are well known and frequently discussed, a significant amount of gas turbines and centrifugal compressors are used in oil and gas applications. In this tutorial such applications and the role of turbomachinery are explained.

Tutorial participants will learn:

• The type of applications
• How turbomachinery is adapted and controlled
• The necessary support systems

Experienced practitioners who construct complex simulation models of critical systems know that replicating real-world performance is challenging due to uncertainties in found in simulation and physical tests. It arises from sources like measurement inaccuracies, material properties, boundary and initial conditions, and modeling approximations. Using case studies, this tutorial will introduce probabilistic and Uncertainty Quantification (UQ) methods, benefits, and tools.

UQ is a systematic process that puts error bands on the results by incorporating real world variability and probabilistic behavior into engineering and systems analysis. UQ answers the question: what is likely to happen when the system is subjected to uncertain and variable inputs. Answering this question facilitates significant risk reduction, robust design, and greater confidence in engineering decisions. Modern UQ techniques use powerful statistical models to map the input-output relationships of the system, significantly reducing the number of simulations or tests required to get statistically defensible answers.

Description of the Subject Being Covered

The tutorial will discuss the basic UQ and probabilistic methods, such as Gaussian processes, polynomial chaos expansion, sparse grids, Latin hypercube designs, model calibration, model validation, sensitivity analysis, and how to account for aleatoric and epistemic uncertainties. This course will also discuss the broad applications these probabilistic techniques have in analyzing numerous forms of engineering systems including Digital Thread/Digital Twins.

Key Learning Objectives

1. Basics of common UQ and probabilistic methods
2. How to apply UQ methods to an engineering system
3. How to use UQ techniques to save design cycle time and computational resources
4. How to develop a robust and reliable design with UQ techniques
5. How to interpret UQ results when making decisions

This tutorial of basics addresses requirements for and selection of materials to withstand the high temperature and high-pressure conditions applicable to components performing in supercritical carbon dioxide environments. A reference plant is identified with operating conditions for supercritical carbon dioxide unique components. Alloys that are likely to be suitable for these conditions are described along with available mechanical and metallurgical data on their properties, as well as additional data that may be required to fully qualify them for the components under the desired service conditions.

The tutorial draws from materials development that has been underway for well over a decade for the next generation Advanced Ultra Supercritical Steam (A-USC) power plants where the need for high temperature (approximately 760 C) materials was recognized and rigorous data were developed, especially to meet ASME code requirements for long term creep and thermal fatigue. Applicability of the data for supercritical carbon dioxide environment are examined. Ongoing efforts, specifically related to effects on materials properties under the oxidizing conditions of supercritical carbon dioxide are summarized.

The tutorial is an essential introduction for designers, materials scientists and engineers in the supercritical carbon dioxide application space, especially in the aggressive high temperature/pressure and oxidation environments.

Supercritical CO2 based power cycles provide significant efficiency and cost of electricity benefits to waste heat, thermal solar, nuclear, ship-board propulsion and fossil fuel power generation applications. They also provide for separation, compression, transportation, and storage (geologic) of CO2 from fossil fuel power plants. The approach to geologic storage of CO2 benefits greatly from the existing technology and knowledge amassed around CO2 utilization and management in the oil & gas industry. While the end goals of the CO2 based power cycles and the CO2 storage applications are different, the properties of the working fluid, thermodynamics, technology and machinery used for these applications are very similar. The confluence of interests related to the use and management of supercritical CO2 has created an imperative to further the understanding of these applications. The Supercritical CO2 Power Cycle committee organizes sessions that focus on the dissemination of machinery and cycle related technologies of sCO2 power plant applications.

Classic gas turbine design relies on the definition of a design point, and the subsequent assessment of the design on a range of off-design conditions. With this approach, it is however difficult to capture the contradicting requirements on the full operating envelope. Thus, practical design efforts often rely on various multi-point design approaches. We introduce cycle design based on such multi-point design approaches in this tutorial.

The session includes a Tutorial of Basics titled "Recent developments in wind turbine technology and research", which is aimed at providing an overview on the status of wind energy to increase the awareness of the engineering community toward this technology. This is particularly important since wind energy will represent one of the pillars of the future energy mix, reaching something in the order between one-fourth and one-third of total production. Special focus will be given to wind turbine technology, showing the current design trends and perspectives, in order to suggest possible research direction to attendants willing to work on the largest rotating machines on Earth.