AOI 1: Hydrogen Combustion Fundamentals for Gas Turbines

Performer: Georgia Tech Research Corporation

Title: Ignition, Turbulent Flame Speeds, and Emissions, from High Hydrogen Blended Fuels

Funding: Federal: $799,997.00; Applicant: $200,002.00; Total: $999,999.00

Georgia Tech Research Corporation (Atlanta, GA) will develop a foundational understanding of key kinetic, flame propagation, and emissions characteristics of high-hydrogen fuels at gas turbine relevant conditions. Data will be gathered under realistic conditions using nationally distinctive facilities—including state-of-the-art high-pressure shock tube and turbulent flame facilities—to bridge knowledge gaps in fundamental combustion properties needed to develop high-hydrogen gas turbines. High-quality experimental data will serve as a foundation for developing and validating reduced chemical kinetic models and turbulent flame models for high-hydrogen containing fuel combustion. Measurements will focus on quantifying autoignition, laminar flame speeds, turbulent flame speeds, and turbulent flame emissions. In particular, the team will measure autoignition delays and laminar flame propagation speeds at high preheating conditions in Georgia Tech’s high-pressure shock tube, and will use a previously developed, high-pressure turbulent flame rig to measure turbulent flame speeds and emissions at different turbulence levels. The fundamental data obtained will be used to validate and optimize existing kinetic models. A reduced kinetic model, including a NOx module, will be developed and disseminated to original equipment manufacturers (OEMs) and other users in academia. A reliable and comprehensive database developed at realistic gas turbine conditions could help OEMs develop combustors for these contemplated fuel blends. The proposed research will also result in a reduced and validated chemical kinetic mechanism—including NOx sub-mechanism—to help OEMs model combustors with significantly reduced computation time. In addition, extensive involvement of undergraduate and graduate students in the research will significantly contribute toward meeting the needs of the gas turbine industry for highly qualified engineers.


Performer: The University of Central Florida Board of Trustees

Title: Fundamental Experimental and Numerical Combustion Study of H2 Containing Fuels for Gas Turbines

Funding: Federal: $800,000.00; Applicant: $246,929.00; Total: $1,046,929.00                                                                                               

University of Central Florida (Orlando, FL) researchers will conduct fundamental experimental and numerical investigations that cover previously unexplored H2 containing fuel blends and conditions of interest. The choice of mixtures, diluents, and conditions will support combustors being developed and targeted by various original equipment manufacturers. Expected results include autoignition characteristics, NO and CO time-histories, laminar and turbulent burning velocities, strain rates and their relationship to NOx, the impact of preferential diffusion on combustion characteristics, and an understanding of flashback in turbulent boundary layers through high-fidelity simulations. The shock tube technique will be used to collect autoignition times and species time-histories through laser absorption spectroscopy, a constant-volume chamber, and high-speed schlieren imagery to obtain laminar burning velocities. A counter-flow flame experiment will be conducted to understand the strain rate/NOx relationship. A detailed chemical kinetic mechanism will be updated to improve its prediction of fuel oxidation and NOx under conditions relevant to combustors. The rate constants of important reactions will be estimated using the quantum chemistry approach. Further, a novel approach that accounts for turbulence and chemistry interactions will be used to reduce the detailed chemical kinetic mechanism generated in this work. Direct numerical simulations will be performed to investigate the significance of preferential diffusion and the need to upgrade existing combustion models to improve their predictability. Large-Eddy Simulations will be performed to investigate the impact of mixture concentrations, flow, and boundary conditions on turbulent boundary layer flashback. Finally, a deep-learning Artificial Intelligence model will be pursued for rapid analysis of detailed fundamental combustion characteristics that support the design and troubleshooting process of H2-containing fuel combustor development. The experimental results will serve as validation targets for the computational portions of this application.


Performer: San Diego State University Foundation

Title: Development of Design Practices for Additively Manufactured Micro-Mix Hydrogen Fueled Turbine Combustors with High-Fidelity Simulation Analysis, Reduced Models and Testing

Funding: Federal: $600,000.00; Applicant: $150,000.00; Total: $750,000.00                                                                                                   

San Diego State University (San Diego, CA) researchers, with partner Solar Turbines Inc., propose a collaborative university/ original equipment manufacturer (OEM) simulation and test program to advance the design of additively manufactured (AM) hydrogen micromix turbine combustors in industrial gas turbines. Because of the combined novelty of hydrogen fuels and AM, no good practice exists for OEM engineers to design robust AM hydrogen combustors. This application aims to develop a generalized modeling framework to predict the effect of geometric design and manufacturing anomalies of hydrogen fuel injectors on mixing, flow rates, pressure losses, heat transfer and flame stability. A chemically reacting flow computation of a single injector array injection into cross airflow above a smooth wall will set a baseline. The effect of several injector and combustor configurations of increasing complexity with multiple injector arrays and wall roughness will be systematically investigated. Design rules and reduced models will be formulated by combining high fidelity simulations of chemically reacting flow, stochastic modeling techniques, reduced modeling though machine learning and testing of injector configurations. These can be used in an industrial setting to predict the aerodynamic and combustion characteristics in hydrogen turbine combustors based upon which design decisions are made.



AOI 2: Hydrogen Combustion Applications for Gas Turbines    

Performer: Purdue University

Title: Investigation of Flame Structure for Hydrogen Gas Turbine Combustion

Funding: Federal: $800,000.00; Applicant: $200,696.00; Total: $1,000,696.00                                                                                                  

Purdue University (West Lafayette, IN) researchers will investigate flame structure and dynamics for gas turbine combustion with hydrogen and another hydrogen-based fuel—ammonia—and with mixtures of these fuels with natural gas. The researchers will explore processes such as flame stabilization, ignition, and flashback, and characterize combustion efficiency and pollutant emissions under combustion conditions characteristic of commercial aeroderivative and heavy-duty F- and H-class gas-turbine systems. The research will focus on additive manufacturing of a multi-stage, multi-tube micro-mixing (M3) injector with straight channels to carry the heated air and featuring staged transverse jet injection of fuels to vary the degree of premixing at the channel exit. The system will be configured so that any of the three fuels—hydrogen, ammonia or natural gas, or their blends—can be injected at multiple injection locations. The experiments will be performed in the Combustor Rig for Advanced Diagnostics (COMRAD) test rig developed in collaboration with and with funding from General Electric. The study will be performed with the M3 injector in two test-article configurations, all anchored to the COMRAD test rig: one for steady state operation for flame structure and emissions characterization, and another for combustion dynamics characterization with well-defined acoustic boundaries. Flame structure and dynamics will be investigated using several laser diagnostics including dual-pump coherent anti-Stokes Raman scattering (CARS), ultrahigh-speed particle imaging velocimetry, and planar laser-induced fluorescence. The team proposes to perform line CARS for temperature measurements and for concentration measurements of species such as hydrogen, oxygen, carbon dioxide, and water. In addition, probe sampling of the flame gases will be performed to determine the combustion efficiency and measure pollutant emissions.


Performer: The Ohio State University

Title: Hydrogen Fuel Effects on Stability and Operation of Lean-Premixed and Staged Gas Turbine Combustors

Funding: Federal: $800,000.00; Applicant: $112,500.00; Other: $112,439.00; Total: $1,024,939.00                                                                          

Ohio State University (Columbus, OH) researchers propose a joint experimental-computational program to advance high-hydrogen content operation of gas turbines. The main objectives are to (1) use advanced laser diagnostics to conduct simultaneous measurements of multiple flame related quantities to study flameholding, flashback, and axial fuel staging; (2) develop a comprehensive suite of computational models to simulate unsteady and transient processes related to flame stabilization and flashback;  and (3) combine experiments and simulations to characterize operability and operational limits for a multi-tube primary burner with axial fuel staging design. The research team will use hydrogen/methane mixtures at engine-relevant conditions to study design issues critical to low-NOx multi-tube burner technology. Using canonical test configurations and multi-parameter time-resolved laser diagnostic measurements, flame processes in jets-in-crossflow configurations will be studied. In particular, the effects of flow properties (momentum, fuel composition, crossflow thermochemical composition) will be used to understand flame stabilization. Similarly, boundary layer flashback dynamics in narrow channels will be studied. Large eddy simulation-based modeling of gas turbines will be pursued, including development of flame-generated manifolds for combustion description, anisotropic near-wall models to describe flame propagation in boundary layers, and techniques for extracting models from high-fidelity direct numerical simulations. Validated models will be used to study the design space to understand operational limits for a model gas turbine with multi-tube burner and axial fuel staging. The proposed effort involves a close collaboration with GE Power personnel who will serve as industrial advisors, provide guidance, and help transition tools to industry. This effort will advance the combustor concepts from TRL 1 to TRL 3. Other elements (diagnostics, tools) will be advanced to TRL 2-3.


Performer: The Regents of the University of California, Irvine

Title: Development and Application of Multipoint Array Injection Concepts for Operation of Gas Turbines on Hydrogen Containing Fuels

Funding: Federal: $800,000.00; Applicant: $200,000.00; Total: $1,000,000.00                                                                                                 

University of California, Irvine (Irvine, CA) will partner with Solar Turbines, Inc., and Collins Aerospace to (1) adapt advanced liquid fuel injectors designed by Collins Aerospace for aero engines to accommodate injection of hydrogen/hydrogen natural gas blends, (2) demonstrate their operation using experiments from laboratory scale model combustor configurations at elevated pressures and temperatures at UC Irvine, and (3) develop a design for test hardware that can be demonstrated at engine conditions in a test rig demonstration at Solar Turbines. The development of the hydrogen injector/array concepts will be led by Collins Aerospace who will use experience and simulations to produce a set of test hardware. The test hardware will be evaluated at UC Irvine at both ambient and elevated pressure conditions. The hardware configurations will be screened for stability, flashback, and reaction structure. In addition, emissions performance will be documented. Data suitable for simulation validation will also be obtained. These results will guide the design of a test module that will be ready for testing under a subsequent project. The 3-year project is expected to bring the TRL of this technology from 2 to 4. The results will set the foundation for further development of the technology for use with high hydrogen content fuels for power generating gas turbines.



AOI 3: Hydrogen-Air Rotating Detonation Engines

Performer: The University of Alabama

Title: A Robust Methodology to Integrate Rotating Detonation Combustor with Gas Turbine to maximize

Pressure Gain

Funding: Federal: $800,000.00; Applicant: $151,567.00; Other: $49,774.00; Total: $1,001,341.00                                                                               

University of Alabama (Tuscaloosa, AL) will partner with Virginia Polytechnic Institute and State University, Aerojet Rocketdyne, Inc., Kulite Semiconductor Products, Inc., and Navy Research Lab to develop a robust methodology to integrate a rotating detonation combustor (RDC) with a gas turbine, and to identify the impact of loss mechanisms on detonation performance in the RDC. Hydrogen and hydrogen-methane fuel mixtures at conditions relevant to F-class gas turbine engines will be used. The research team will minimize flow unsteadiness at the RDC exit and maximize pressure gain by applying computational and experimental techniques to optimize the flow path in an annular RDC channel by strategically constricting the flow area to improve the stability of detonation and to weaken the oblique shock wave(s) for higher performance. In addition, the team will apply computational and experimental techniques to optimize and integrate the RDC with a diffuser for F-class gas turbines. The methodology developed will be applicable to aeroderivative gas turbines. Lastly, computational and experimental techniques will be applied to an optimized RDC-diffuser design to quantify the impact of loss mechanisms in the combustion process associated with non-ideal mixing, mixed mode combustion (deflagration/detonation), and wave mode/numbers in the RDC. Computational fluid dynamics (CFD) simulations will be performed and validated against detailed experimental data sets. A Design of Experiments approach will be applied to optimize geometric parameters of the RDC annular flow path and the integrated RDC-diffuser design. In addition, CFD simulations on the fully integrated RDC-diffuser design will be performed at select operating conditions to quantify the impact of loss mechanisms in the combustion process. Experiments will be performed using RDC and integrated RDC-diffuser system. A plenum with a backpressure plate will be used to simulate the turbine flow path. Pressure probes, ion-probes, dynamic pressure probes, and advanced high-speed, diagnostic techniques including particle image velocimetry and rainbow schlieren deflectometry will be used to quantify the flow unsteadiness, pressure gain (loss), and to generate a robust validation data set.


Performer: Purdue University

Title: Physics-based integration of H2-Air Rotating detonation into Gas Turbine Power Plant (HydrogenGT)

Funding: Federal: $800,000.00; Applicant: $200,003.00; Other: $50,000.00; Total: $1,050,003.00                                                                               

Purdue University (West Lafayette, IN) and a team of university and industry partners will develop a novel, compact combustor-diffuser-turbine strategy to transition high-speed, unsteady flow from rotating detonation combustors (RDCs) to industrial turbines. Physics-based-models will be developed to scale results to an F-class turbine, culminating in an experimental/numerical methodology to establish a successful architecture and the relevant nondimensional parameters for Powerplant operation at high thermodynamic cycle efficiency.  The specific project objectives are to (1) characterize the influence of various loss mechanisms on the performance metrics of RDC-turbine systems via integration of experimental and computational studies and (2) develop the efficient transition of the high-Mach-number, unsteady RDC outlet into a turbine rotor for reliable work extraction. The research methodology involves three tasks: loss budgeting in a combustor with a downstream transition element and NGV; demonstrating the coupling of the RDC – flow transition and NGV turbine to produce work; and scaling experimental and computational studies to F-class and aero-derivative class RDE gas turbine integrated system. The proposed approach will rely on a combined experimental and computational effort. This project capitalizes on (1) exceptional experimental facilities for testing RDCs at high-pressure and a state-of-the-art tri-sonic turbine facility; (2) a balanced team of university experts in rotating detonation combustors, high-fidelity computational fluid dynamics, advanced high-speed laser diagnostics, surface sensors, and flow probes, diffuser design, and turbine design and testing; and (3) support from Rolls-Royce Liberty Works (donating an M250 engine) and Aerojet Rocketdyne. In addition, experts from Technical University of Berlin and Politecnico di Torino will commit complementary support of graduate students and mentoring. This research will have a significant impact by leading the transition of university research on hydrogen RDC-based gas turbines (HydrogenGT) from TRL2 to TRL4 and, with the help of OEM partners, to TRL5.