Reaction Zone Characterization in a Gas Turbine Model Validation Combustor

2013 ◽  
Author(s):  
Clinton R. Bedick ◽  
Nathan T. Weiland ◽  
Peter A. Strakey
Keyword(s):  
Gas Turbine ◽  
Model Validation ◽  
Reaction Zone ◽  
Bluff Body ◽  
Air Flow ◽  
Flame Surface ◽  
Swirl Burner ◽  
Validation Data ◽  
Global Emissions ◽  
Swirling Air Flow

The Enclosed Sydney Swirl Burner (ESSB), a half-scale version of the Sydney Swirl Burner coupled to an optically accessible combustion chamber, was recently constructed at the National Energy Technology Laboratory for the purpose of generating global emissions and model validation data in a configuration relevant to industrial and gas turbine combustion. The ESSB is capable of diffusion flame combustion of CH4/H2/inert fuel mixtures in highly swirling air flow over a bluff body, and can produce a wide variety of flame types and structures for study. Based on stability characteristics and global emissions data, three flames were chosen for reaction zone characterization: a non-swirling 1:1 H2:CH4 flame, a high-swirl 1:1 H2:CH4 flame, and a lifted, V-shaped flame of CH4 with a swirling air flow. Reaction zone characterization is performed via planar OH-PLIF measurements taken at multiple locations within the square cross-section of the ESSB. Mean flame surface locations are described, and maps of flame front probabilities are generated for each of the flames. Measurements indicate quenching in the high strain region in the neck above the bluff body for the non-swirling flame, wall-quenching for the swirling flames, and OH production below the lifted flame that helps sustain the reaction zone. The OH-PLIF data, as well as global emissions and thermal boundary condition measurements for these flames, are freely available for model validation purposes.

Flow Field of a Model Gas Turbine Swirl Burner

2012 ◽  
Vol 622-623 ◽  
pp. 1119-1124 ◽  
Author(s):  
Cheng Tung Chong ◽  
Simone Hochgreb
Keyword(s):  
Flow Field ◽  
Radial Velocity ◽  
Gas Turbine ◽  
Air Flow ◽  
Atmospheric Condition ◽  
Flow Fields ◽  
Swirl Flow ◽  
Scale Model ◽  
Swirl Burner ◽  
Swirling Air Flow

The flow field of a lab-scale model gas turbine swirl burner was characterised using particle imaging velocimetry (PIV) at atmospheric condition. The swirl burner consists of an axial swirler, a twin-fluid atomizer and a quartz tube as combustor wall. The main non-reacting swirling air flow without spray was compared to swirl flow with spray under unconfined and enclosed conditions. The introduction of liquid fuel spray changes the flow field of the main swirling air flow at the burner outlet where the radial velocity components are enhanced. Under reacting conditions, the enclosure generates a corner recirculation zone that intensifies the strength of the radial velocity. Comparison of the flow fields with a spray flame using diesel and palm biodiesel shows very similar flow fields. The flow field data can be used as validation target for swirl flame modelling.

Flame stability of a bluff-body combustor with swirling air flow

2004 ◽  
Vol 2004.I (0) ◽  
pp. 147-148
Author(s):  
Kazuya UCHIDA ◽  
Genryu OOE ◽  
Tatsuo NISHIMURA ◽  
Hideo KAWAHARA
Keyword(s):  
Bluff Body ◽  
Air Flow ◽  
Flame Stability ◽  
Swirling Air Flow

scholarly journals Wall Temperature Measurements in Gas Turbine Combustors With Thermographic Phosphors

2018 ◽  
Vol 141 (4) ◽  
Author(s):  
Patrick Nau ◽  
Zhiyao Yin ◽  
Oliver Lammel ◽  
Wolfgang Meier
Keyword(s):  
Gas Turbine ◽  
Wall Temperature ◽  
Gas Turbines ◽  
High Speed ◽  
Bluff Body ◽  
Temperature Measurements ◽  
Transient Temperature ◽  
High Time Resolution ◽  
Ceramic Surface ◽  
Precessing Vortex Core

Phosphor thermometry has been developed for wall temperature measurements in gas turbines and gas turbine model combustors. An array of phosphors has been examined in detail for spatially and temporally resolved surface temperature measurements. Two examples are provided, one at high pressure (8 bar) and high temperature and one at atmospheric pressure with high time resolution. To study the feasibility of this technique for full-scale gas turbine applications, a high momentum confined jet combustor at 8 bar was used. Successful measurements up to 1700 K on a ceramic surface are shown with good accuracy. In the same combustor, temperatures on the combustor quartz walls were measured, which can be used as boundary conditions for numerical simulations. An atmospheric swirl-stabilized flame was used to study transient temperature changes on the bluff body. For this purpose, a high-speed setup (1 kHz) was used to measure the wall temperatures at an operating condition where the flame switches between being attached (M-flame) and being lifted (V-flame) (bistable). The influence of a precessing vortex core (PVC) present during M-flame periods is identified on the bluff body tip, but not at positions further inside the nozzle.

Temperature measurements of the bluff body surface of a Swirl Burner using phosphor thermometry

2014 ◽  
Vol 161 (11) ◽  
pp. 2842-2848 ◽  
Author(s):  
Matthias Euler ◽  
Ruigang Zhou ◽  
Simone Hochgreb ◽  
Andreas Dreizler
Keyword(s):  
Body Surface ◽  
Bluff Body ◽  
Temperature Measurements ◽  
Swirl Burner ◽  
Phosphor Thermometry

Boundary Layer Flashback Limits of Hydrogen-Methane-Air Flames in a Generic Swirl Burner at Gas Turbine Relevant Conditions

2020 ◽  
Author(s):  
Dominik Ebi ◽  
Peter Jansohn
Keyword(s):  
Boundary Layer ◽  
Gas Turbine ◽  
Wall Temperature ◽  
Gas Turbines ◽  
High Speed ◽  
Cooling System ◽  
Atmospheric Conditions ◽  
Preheat Temperature ◽  
Swirl Burner ◽  
Wide Range

Abstract Operating stationary gas turbines on hydrogen-rich fuels offers a pathway to significantly reduce greenhouse gas emissions in the power generation sector. A key challenge in the design of lean-premixed burners, which are flexible in terms of the amount of hydrogen in the fuel across a wide range and still adhere to the required emissions levels, is to prevent flame flashback. However, systematic investigations on flashback at gas turbine relevant conditions to support combustor development are sparse. The current work addresses the need for an improved understanding with an experimental study on boundary layer flashback in a generic swirl burner up to 7.5 bar and 300° C preheat temperature. Methane-hydrogen-air flames with 50 to 85% hydrogen by volume were investigated. High-speed imaging was applied to reveal the flame propagation pathway during flashback events. Flashback limits are reported in terms of the equivalence ratio for a given pressure, preheat temperature, bulk flow velocity and hydrogen content. The wall temperature of the center body along which the flame propagated during flashback events has been controlled by an oil heating/cooling system. This way, the effect any of the control parameters, e.g. pressure, had on the flashback limit was de-coupled from the otherwise inherently associated change in heat load on the wall and thus change in wall temperature. The results show that the preheat temperature has a weaker effect on the flashback propensity than expected. Increasing the pressure from atmospheric conditions to 2.5 bar strongly increases the flashback risk, but hardly affects the flashback limit beyond 2.5 bar.

An Onion Peeling Reconstruction of the Spatial Characteristics of Entropy Waves in a Model Gas Turbine Combustor

2017 ◽  
Author(s):  
Dominik Wassmer ◽  
Felix Pause ◽  
Bruno Schuermans ◽  
Christian Oliver Paschereit ◽  
Jonas P. Moeck
Keyword(s):  
Gas Turbine ◽  
Reaction Zone ◽  
Equivalence Ratio ◽  
Acoustic Noise ◽  
Accurate Determination ◽  
Time Of Flight ◽  
Spark Discharge ◽  
Turbine Stage ◽  
Radial Temperature ◽  
Reconstructed Temperature

Entropy noise affects thermoacoustic stability in lean pre-mixed gas turbine combustion chambers. It is defined as acoustic noise that is emitted at the first turbine stage due to the acceleration of entropy waves that are advected from the reaction zone in the combustor to the turbine inlet. These non-isentropic temperature waves are caused by equivalence ratio fluctuations which are inherently present in a technically premixed combustion system. To experimentally study the generation and transport of entropy waves, an estimation of the spatial distribution of the entropy spots is highly valuable as it allows the accurate determination of the cross-section averaged entropy, which is the relevant quantity for the formation mechanism of entropy noise at the turbine stage. In this work, a time-of-flight based temperature measurement method is applied to a circular combustion test rig equipped with a premixed swirl-stabilized combustor. Downstream of the burner, an electric spark discharge is employed to generate a narrow acoustic pulse which is detected with a circumferentially arranged microphone array. The measured time of flight of the acoustic signal corresponds to the line-integrated inverse of the speed of sound between the acoustic source and each microphone. By modulating a share of the injected gaseous fuel, equivalence ratio fluctuations are generated upstream of the reaction zone and consequently entropy spots are advected through the axial measurement plane. The spark discharge is triggered at distinct phase angles of the entropy oscillation, thus allowing a time resolved-analysis of the thermo-acoustic phenomenon. Estimating the spatial temperature distribution from the measured line integrated inverse speed of sounds requires tomographic reconstruction. A Tikhonov regularized Onion Peeling is employed to deduce radial temperature profiles. To increase the number of independent data, the spark location is radially traversed, which enhances the resolution of the reconstructed temperature field. A phantom study is conducted, which allows the assessment of the capabilities of the reconstruction algorithm. By means of the reconstructed radial entropy field, spatially resolved entropy waves are measured and their amplitudes and phases are extracted. The characteristics of the entropy waves measured in this way correspond well to former studies.

Laser-induced incandescence measurements in the reaction zone of a model gas turbine combustor

2002 ◽  
Author(s):  
M. Brown ◽  
T. Meyer ◽  
J. Gord ◽  
V. Belovich ◽  
W. Roquemore
Keyword(s):  
Gas Turbine ◽  
Reaction Zone ◽  
Gas Turbine Combustor ◽  
Laser Induced Incandescence ◽  
Model Gas Turbine Combustor

scholarly journals Heat Transfer Enhancement in Air Cooled Gas Turbine Blade Using

2021 ◽  
Vol 8 (3) ◽  
pp. 52-69
Author(s):  
Dr. Farhan Lafta Rashid Rashid ◽  
Dr. Haider Nadhom Azziz Azziz ◽  
Dr. Emad Qasem Hussein Hussein
Keyword(s):  
Temperature Distribution ◽  
Gas Turbine ◽  
Turbine Blade ◽  
Air Temperature ◽  
Air Flow ◽  
Three Dimensions ◽  
Internal Diameter ◽  
Wall Surface ◽  
Gas Turbine Blade ◽  
Ansys Fluent

In this paper, an investigation of using corrugated passages instead of circular crosssection passages was achieved in conditions simulate the case in the gas turbine blade coolingusing ANSYS Fluent version (14.5) with Boundary conditions: inlet coolant air temperature of300 K with different air flow Reynolds numbers (191000, 286000 and 382000). Thesurrounding constant hot air temperatures was (1700 K). The numerical simulations was done bysolving the governing equations (Continuity, Reynolds Averaging Navier-stokes and Energyequation) using (k-ε) model in three dimensions by using the FLUENT version (14.5). Thepresent case was simulated by using corrugated passage of 3 m long, internal diameter of 0.3 m,0.01 m groove height and wall thickness of 0.01 m, was compared with circular cross sectionpipe for the same length, diameter and thickness. The temperature, velocity distributioncontours, cooling air temperature distribution, the inner wall surface temperature, and thermalperformance factor at the two passages centerline are presented in this paper. The coolant airtemperature at the corrugated passage centerline was higher than that for circular one by(12.3%), the temperature distribution for the inner wall surface for the corrugated passage islower than circular one by (4.88 %). The coolant air flow velocity seems to be accelerated anddecelerated through the corrugated passage, so it was shown that the thermal performance factoralong the corrugated passage is larger than 1, this is due to the fact that the corrugated wallscreate turbulent conditions and increasing thermal surface area, and thus increasing heat transfercoefficient than the circular case.

Investigations of air flow behavior past a conical bluff body using particle imaging velocimetry

2015 ◽  
Vol 56 (11) ◽  
Author(s):  
Marcin Dutka ◽  
Mario Ditaranto ◽  
Terese Løvås
Keyword(s):  
Bluff Body ◽  
Flow Behavior ◽  
Air Flow ◽  
Particle Imaging Velocimetry ◽  
Particle Imaging

4D Measurements and Analysis of Heat Release Rate in a Model Gas Turbine Combustor

2020 ◽  
Author(s):  
Rongxiao Dong ◽  
Qingchun Lei ◽  
Yeqing Chi ◽  
Qun Zhang ◽  
Wei Fan
Keyword(s):  
Heat Release ◽  
Gas Turbine ◽  
Surface Area ◽  
Heat Release Rate ◽  
Release Rate ◽  
Flame Surface ◽  
Global Instability ◽  
Gas Turbine Combustor ◽  
Model Gas Turbine Combustor ◽  
Edge Contours

Abstract Time-resolved volumetric measurements (4D measurements) were performed to study the heat release rate characteristics in a model gas turbine combustor at 10 kHz. For this purpose, a high-speed camera combined with an image intensifier and a set of customized fiber probes were employed to continuously capture the CH* chemiluminescence signals from nine different viewing angles. Based on the measurements, the computed tomography program was performed to reconstruct the shot-to-shot 3D distributions of the CH* signals. Specific focuses have been made to demonstrate the capabilities of the current tomographic technique in applications of a realistic combustor, in which the full optical access was usually not available for every viewing angle. The results showed that the 3D reconstruction can successfully retrieval the flame edge contours rather than the signal intensity. The flame surface area was then calculated based on the reconstructed flame edge contours and used to infer the heat release rate. The fluctuation of global/local flame surface area indicated that there existed distinct difference between the global instability and local instabilities at various locations in the non-symmetric combustor. The global instability appears to be an integration of those local instabilities.

Sign in / Sign up

Export Citation Format

Share Document