Article
Energy & Fuels
Zehua Zhang, Abouelmagd Abdelsamie, Cheng Chi, Dominique Thevenin, Kai H. Luo
Summary: This study numerically investigated the flame anchoring of a hydrogen-rich jet injecting perpendicularly into hot vitiated crossflow. The flame was found to be anchored around the jet exit and downstream only on the windward side. Diffusion flame was dominant, though some premixed or partially premixed regions were found on the leeward side due to turbulent mixing.
Article
Energy & Fuels
Michelle Otero, Tommy Genova, Bernhard Stiehl, Anthony J. Morales, Scott Martin, Kareem A. Ahmed
Summary: This study experimentally investigates the effects of elevated combustor pressures on a lean premixed reacting methane/air jet injected into a lean vitiated crossflow. The results show that higher pressure leads to greater jet penetration, but a decrease in flame liftoff point and ignition delay time. Emissions measurements confirm the increase in NOx with pressure, but the staged configuration reduces global outlet emissions.
JOURNAL OF ENERGY RESOURCES TECHNOLOGY-TRANSACTIONS OF THE ASME
(2022)
Article
Energy & Fuels
Bernhard Stiehl, Tommy Genova, Michelle Otero, Scott Martin, Kareem Ahmed
Summary: In this study, three reacting jet-in-crossflow methane/air flames were numerically investigated in a lean axially staged combustor at a pressure of five atmospheres, focusing on predicting and verifying NOx formation. By adjusting fuel stratification, the global emission benefits at different equivalence ratios were studied, showing potential high axial NO production at elevated headend temperature levels.
JOURNAL OF ENERGY RESOURCES TECHNOLOGY-TRANSACTIONS OF THE ASME
(2021)
Article
Thermodynamics
Xianglong Zheng, Fulin Lei, Yan Xiong
Summary: This study uses the Scale-Adaptive Simulation (SAS) method to simulate Jet in crossflow (JIC) and compares it with the traditional Reynolds-averaged Navier Stokes (RANS) method. The results show that the SAS method can predict the flow characteristics and flame interaction more accurately. Additionally, numerical studies suggest that arranging non-uniform fuel injection can effectively decrease the wall temperature.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2022)
Article
Energy & Fuels
Zhen Wang, Yayao Wang, Xunchen Liu
Summary: This study proposed a novel twin-nozzle configuration for secondary fuel injection, which can control the injection of fuel and air separately and allow flame organization. By using high-speed CH* imaging, the effects of different parameters on flame dynamical characteristics were investigated, revealing certain patterns.
JOURNAL OF ENERGY RESOURCES TECHNOLOGY-TRANSACTIONS OF THE ASME
(2022)
Article
Engineering, Aerospace
Rahand Dalshad, Tobias Sander, Lukas Fischer, Paola Breda, Michael Pfitzner
Summary: This work investigates near-wall reacting jets in different engineering applications. Experimental investigations and computational simulations with a combustion model are used to study the characteristics of reacting gaseous fuel jets injected into a hot oxygen-rich cross-flow. The study reveals differences in ignition behavior, surface heat flux, and reaction zone shapes among different fuels, and shows potential discrepancies between simulations and experiments in combustion temperature estimation.
AEROSPACE SCIENCE AND TECHNOLOGY
(2023)
Article
Thermodynamics
Zhen Wang, Yayao Wang, Xunchen Liu
Summary: Secondary fuel injection has an impact on the combustion structure and flame dynamics in axial fuel staging gas turbines. In this study, a front-fuel rear-air twin-nozzle configuration is examined, where the fuel and air can be injected independently to stabilize the lifted flame front and control the jet trajectory. Experimental techniques including formaldehyde planar laser induced fluorescence thermometry, particle image velocimetry, and chemiluminescence are used to investigate the temperature field, flow field dynamics, and combustion mode in the presence of secondary air injection.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Energy & Fuels
Qiuping Xiao, Jun Cheng, Bo Zhang, Jian Zhou, Wanghua Chen
Summary: This study investigates the interaction between JICF and a deflagrated flame in a stoichiometric hydrogen-air mixture. The results show that introducing JICF promotes flame speed, particularly at higher initial pressure. By adjusting pressure ratio and time delay, the flame speed can be optimized within certain ranges.
Article
Energy & Fuels
Bernhard Stiehl, Michelle Otero, Tommy Genova, Scott Martin, Kareem Ahmed
Summary: This paper investigates the pressure dependency of a lean premixed jet injected into a lean vitiated crossflow, and discusses the reasons for the production of nitrogen oxides at high pressure. By combining experimental data with computational fluid dynamics models, the analysis validates the relationship between flame stabilization and pressure.
JOURNAL OF ENERGY RESOURCES TECHNOLOGY-TRANSACTIONS OF THE ASME
(2021)
Article
Mechanics
Vedanth Nair, Matthew Sirignano, Benjamin L. Emerson, Timothy C. Lieuwen
Summary: This study investigates the stability characteristics of shear layer vortices in a reacting jet in crossflow by using particle image velocimetry. The effects of flame position, momentum flux ratio, and density ratio are analyzed. It is found that the stability behavior depends on the flame position and the S and J values. A unified scaling model is proposed to explain the frequency and stability characteristics.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
Dong-hyuk Shin, A. J. Aspden, Vlad Aparece-Scutariu, Edward S. S. Richardson
Summary: Scalar mixing in decelerating turbulent round jet is studied using direct numerical simulation. The study aims to determine and model new self-similar states in the unsteady flow and predict the evolution of relevant flow quantities along the centerline. The mass fraction of jet fluid and the fluid residence time show self-similar radial profiles in statistically stationary turbulent jets. However, during the deceleration wave, a different self-similar state is observed for the two scalar variables. The behavior of the jet fluid mass fraction and the mass-weighted stream age of jet fluid changes in the decelerating jet compared to the steady-state jet.
Article
Chemistry, Physical
Simone Castellani, Roberto Meloni, Stefano Orsino, Naseem Ansari, Rakesh Yadav, Didier Bessette, Isaac Boxx, Antonio Andreini
Summary: This study investigates the multi-regime CH4-H-2 Jet In Crossflow (JICF) flame at gas turbine relevant conditions and predicts the change in flame morphology caused by an increase in hydrogen content using a Flame Index controlled Artificially Thickened Flame Model (ATFM). The numerical prediction shows good agreement with experimental data and provides valuable insights into flame anchoring topology.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Engineering, Multidisciplinary
Hazem S. Gitar, Yehia A. Eldrainy
Summary: Novel combustion techniques, such as colorless distributed combustion (CDC) or flameless combustion (FC), have been investigated to reduce emissions from gas turbines due to strict regulations on harmful emissions. The study examined the impact of factors like air diameter, confinement size, and excess air ratio on recirculation ratio in flameless combustion. Results showed a significant influence of combustor diameter and air jet diameter on NOx emissions.
ALEXANDRIA ENGINEERING JOURNAL
(2021)
Article
Thermodynamics
Xianglong Zheng, Yan Xiong, Yan Liu, Fulin Lei, Yunhan Xiao
Summary: Experimental study on axial-fuel-staged MILD combustor with varying parameters to observe NOx emissions. Found patterns of NOx reduction at higher phi(t) and continuous increase at higher phi(2). Lift-off behavior of reaction region studied, showing impact on mixture dilution and emissions. Supported by opposed-flow flame calculation.
COMBUSTION SCIENCE AND TECHNOLOGY
(2021)
Article
Chemistry, Physical
Jiseop Lee, Nam Il Kim
Summary: Adding hydrogen to methane can reduce CO2 emissions from combustion systems, but it also presents challenges. This study investigated the combustion characteristics of a turbulent fuel jet with coaxial air under elevated pressures. The results identified three clear flame stabilization modes, with the inner-lifted mode demonstrating the best combustion performance.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Engineering, Mechanical
Christopher Douglas, Jamie Lim, Travis Smith, Benjamin Emerson, Timothy Lieuwen, Naibo Jiang, Christopher Fugger, Tongxun Yi, Josef Felver, Sukesh Roy, James Gord
JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER-TRANSACTIONS OF THE ASME
(2019)
Article
Thermodynamics
Sukruth Somappa, Luke Humphrey, Ben Emerson, Tim Lieuwen
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2019)
Article
Thermodynamics
Vedanth Nair, Benjamin Wilde, Benjamin Emerson, Tim Lieuwen
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2019)
Article
Thermodynamics
Matthew D. Sirignano, Vedanth Nair, Benjamin Emerson, Jerry Seitzman, Timothy C. Lieuwen
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2019)
Article
Thermodynamics
T. Yi, B. R. Halls, N. Jiang, J. Felver, M. Sirignano, B. L. Emerson, T. C. Lieuwen, J. R. Gord, S. Roy
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2019)
Article
Thermodynamics
Vedanth Nair, Matthew Sirignano, Benjamin Emerson, Ben Halls, Naibo Jiang, Josef Felver, Sukesh Roy, Jim Gord, Tim Lieuwen
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2019)
Article
Engineering, Mechanical
Nicholas Rock, Ianko Chterev, Benjamin Emerson, Sang Hee Won, Jerry Seitzman, Tim Lieuwen
JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER-TRANSACTIONS OF THE ASME
(2019)
Article
Thermodynamics
Edwin Goh, Matthew Sirignano, James Li, Vedanth Nair, Ben Emerson, Tim Lieuwen, Jerry Seitzman
COMBUSTION AND FLAME
(2019)
Article
Thermodynamics
Nicholas Rock, Ben Emerson, Jerry Seitzman, Tim Lieuwen
COMBUSTION AND FLAME
(2020)
Article
Mechanics
Vishal Acharya, Timothy Lieuwen
JOURNAL OF FLUID MECHANICS
(2020)
Article
Thermodynamics
Vishal Acharya, Timothy C. Lieuwen
Summary: This study investigates the nonlinear response of flames to harmonic forcing, finding that flame responses saturate and exhibit non-monotonic behaviors as disturbance amplitudes increase. The model analysis reveals the conditions for non-monotonic behavior and is applied to measured data, showing parameter regions where such behavior occurs in nonlinear premixed flame calculations.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2021)
Proceedings Paper
Energy & Fuels
M. D. Sirignano, V. Nair, D. Sunkara, B. L. Emerson, J. Seitzman, T. C. Lieuwen
PROCEEDINGS OF THE ASME TURBO EXPO: TURBOMACHINERY TECHNICAL CONFERENCE AND EXPOSITION, 2019, VOL 4B
(2019)
Proceedings Paper
Energy & Fuels
David Noble, Leonard Angello, Scott Sheppard, Jared Kee, Benjamin Emerson, Tim Lieuwen
PROCEEDINGS OF THE ASME TURBO EXPO: TURBOMACHINERY TECHNICAL CONFERENCE AND EXPOSITION, 2019, VOL 3
(2019)
Proceedings Paper
Energy & Fuels
J. Kim, T. Lieuwen, B. Emerson, V. Acharya, D. Wu, R. Mckinney, X. Wang, M. Isono
PROCEEDINGS OF THE ASME TURBO EXPO: TURBOMACHINERY TECHNICAL CONFERENCE AND EXPOSITION, 2019, VOL 4B
(2019)