Interaction of hafnium with hydrogen and nitrogen in the combustion regime

1995 ◽  
Vol 20 (5) ◽  
pp. 391-395 ◽  
Author(s):  
S Dolukhanyan
Keyword(s):  
Combustion Regime

scholarly journals Combustion regime identification from machine learning trained by Raman/Rayleigh line measurements

2020 ◽  
Vol 219 ◽  
pp. 268-274 ◽  
Author(s):  
Kaidi Wan ◽  
Sandra Hartl ◽  
Luc Vervisch ◽  
Pascale Domingo ◽  
Robert S. Barlow ◽  
...  
Keyword(s):  
Machine Learning ◽  
Combustion Regime ◽  
Rayleigh Line

Spray flame structure in conventional and hot-diluted combustion regime

2015 ◽  
Vol 162 (3) ◽  
pp. 759-773 ◽  
Author(s):  
Hugo Correia Rodrigues ◽  
Mark J. Tummers ◽  
Eric H. van Veen ◽  
Dirk J.E.M. Roekaerts
Keyword(s):  
Flame Structure ◽  
Combustion Regime ◽  
Spray Flame

Effects of hydrogen addition on structure and NO formation of highly CO-Rich syngas counterflow nonpremixed flames under MILD combustion regime

2021 ◽  
Vol 46 (17) ◽  
pp. 10518-10534
Author(s):  
Namsu Kim ◽  
Yongmo Kim ◽  
Mohammad Nazri Mohd Jaafar ◽  
Muhammad Roslan Rahim ◽  
Mazlan Said
Keyword(s):  
Combustion Regime ◽  
Nonpremixed Flames ◽  
Hydrogen Addition ◽  
No Formation ◽  
Mild Combustion

scholarly journals Numerical study of flame structure in the mild combustion regime

2015 ◽  
Vol 19 (1) ◽  
pp. 21-34 ◽  
Author(s):  
Amir Mardani ◽  
Sadegh Tabejamaat
Keyword(s):  
Fuel Injection ◽  
Numerical Study ◽  
Flame Structure ◽  
Combustion Regime ◽  
Low Oxygen ◽  
Mixing Rate ◽  
Jet Flame ◽  
Reduced Mechanism ◽  
Mild Combustion ◽  
O2 Concentration

In this paper, turbulent non-premixed CH4+H2 jet flame issuing into a hot and diluted co-flow air is studied numerically. This flame is under condition of the moderate or intense low-oxygen dilution (MILD) combustion regime and related to published experimental data. The modelling is carried out using the EDC model to describe turbulence-chemistry interaction. The DRM-22 reduced mechanism and the GRI2.11 full mechanism are used to represent the chemical reactions of H2/methane jet flame. The flame structure for various O2 levels and jet Reynolds numbers are investigated. The results show that the flame entrainment increases by a decrease in O2 concentration at air side or jet Reynolds number. Local extinction is seen in the upstream and close to the fuel injection nozzle at the shear layer. It leads to the higher flame entertainment in MILD regime. The turbulence kinetic energy decay at centre line of jet decreases by an increase in O2 concentration at hot Co-flow. Also, increase in jet Reynolds or O2 level increases the mixing rate and rate of reactions.

Chemical Kinetic Analysis of a Flameless Gas Turbine Combustor

2008 ◽  
Author(s):  
G. Arvind Rao ◽  
Yeshayahou Levy ◽  
Ephraim J. Gutmark
Keyword(s):  
Combustion Chamber ◽  
Kinetic Analysis ◽  
Gas Turbine ◽  
Flame Temperature ◽  
Plug Flow ◽  
Combustion Process ◽  
Chemical Reactor ◽  
Chemical Kinetic ◽  
Combustion Regime ◽  
Reactor Model

Flameless combustion (FC) is one of the most promising techniques of reducing harmful emissions from combustion systems. FC is a combustion phenomenon that takes place at low O2 concentration and high inlet reactant temperature. This unique combination results in a distributed combustion regime with a lower adiabatic flame temperature. The paper focuses on investigating the chemical kinetics of an prototype combustion chamber built at the university of Cincinnati with an aim of establishing flameless regime and demonstrating the applicability of FC to gas turbine engines. A Chemical reactor model (CRM) has been built for emulating the reactions within the combustor. The entire combustion chamber has been divided into appropriate number of Perfectly Stirred Reactors (PSRs) and Plug Flow Reactors (PFRs). The interconnections between these reactors and the residence times of these reactors are based on the PIV studies of the combustor flow field. The CRM model has then been used to predict the combustor emission profile for various equivalence ratios. The results obtained from CRM model show that the emission from the combustor are quite less at low equivalence ratios and have been found to be in reasonable agreement with experimental observations. The chemical kinetic analysis gives an insight on the role of vitiated combustion gases in suppressing the formation of pollutants within the combustion process.

Reaction times and burning rates for wind tunnel headfires

2003 ◽  
Vol 12 (2) ◽  
pp. 195 ◽  
Author(s):  
Ralph M. Nelson, Jr.
Keyword(s):  
Reaction Time ◽  
Wind Tunnel ◽  
Wildland Fire ◽  
Mass Loss Rate ◽  
Fire Behavior ◽  
Reaction Times ◽  
Reaction Time Data ◽  
Combustion Regime ◽  
Fuel Particle ◽  
Time Data

Catchpole et al. (1998) reported rates of spread for 357 heading and no-wind fires burned in the wind tunnel facility of the USDA Forest Service's Fire Sciences Laboratory in Missoula, Montana for the purpose of developing models of wildland fire behavior. The fires were burned in horizontal fuel beds with differing characteristics due to various combinations of fuel type, particle size, packing ratio, bed depth, moisture content, and wind speed. In the present paper, fuel particle and fuel bed data for 260 heading fires from that study (plus as-yet unreported combustion efficiency and reaction time data) are used to develop models for predicting fuel bed reaction time and mass loss rate. Reaction time is computed from the flameout time of a single particle and fuel bed structural properties. It is assumed that the beds burn in a combustion regime controlled by the rate at which air mixes with volatiles produced during pyrolysis, and that not all air entering the fuel bed reaction zone participates in combustion. Comparison of reaction time and burning rate predictions with experimental values is encouraging in view of the simplified modeling approach and uncertainties associated with the experimental measurements.

scholarly journals Application of a three-step approach for prediction of combustion instabilities in industrial gas turbine burners

2017 ◽  
Vol 1 ◽  
pp. JCW78T
Author(s):  
Dmytro Iurashev ◽  
Giovanni Campa ◽  
Vyacheslav V. Anisimov ◽  
Ezio Cosatto ◽  
Luca Rofi ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Time Lag ◽  
High Amplitude ◽  
Combustion Regime ◽  
Industrial Test ◽  
Distributed Model ◽  
Combustion Instabilities ◽  
Acoustic Oscillations ◽  
Analytical Time

Abstract Recently, because of environmental regulations, gas turbine manufacturers are restricted to produce machines that work in the lean combustion regime. Gas turbines operating in this regime are prone to combustion-driven acoustic oscillations referred as combustion instabilities. These oscillations could have such high amplitude that they can damage gas turbine hardware. In this study, the three-step approach for combustion instabilities prediction is applied to an industrial test rig. As the first step, the flame transfer function (FTF) of the burner is obtained performing unsteady computational fluid dynamics (CFD) simulations. As the second step, the obtained FTF is approximated with an analytical time-lag-distributed model. The third step is the time-domain simulations using a network model. The obtained results are compared against the experimental data. The obtained results show a good agreement with the experimental ones and the developed approach is able to predict thermoacoustic instabilities in gas turbines combustion chambers.

Sign in / Sign up

Export Citation Format

Share Document