scholarly journals Investigations on gas-air mixture formation in the ignition chamber of two-stage combustion chamber using high-speed Schlieren imaging

2017 ◽  
Vol 118 ◽  
pp. 00012 ◽  
Author(s):  
Wojciech Bueschke ◽  
Maciej Skowron ◽  
Krzysztof Wislocki
Keyword(s):  
Combustion Chamber ◽  
High Speed ◽  
Schlieren Imaging ◽  
Mixture Formation ◽  
Two Stage ◽  
Stage Combustion

Study of Sequential Two-Stage Combustion in a Low-Emission Gas Turbine Combustion Chamber

2018 ◽  
Vol 65 (11) ◽  
pp. 806-817 ◽  
Author(s):  
L. A. Bulysova ◽  
A. L. Berne ◽  
V. D. Vasil’ev ◽  
M. N. Gutnik ◽  
M. M. Gutnik
Keyword(s):  
Combustion Chamber ◽  
Gas Turbine ◽  
Two Stage ◽  
Stage Combustion ◽  
Low Emission ◽  
Gas Turbine Combustion

scholarly journals USE OF TWO-STAGE FUEL COMBUSTION TECHNOLOGY TO MINIMIZE HAZARDOUS EMISSIONS AT KAZAKHSTAN TPP

2021 ◽  
Vol 335 (1) ◽  
pp. 74-80
Author(s):  
A.S. Askarova ◽  
P. Safarik ◽  
S.A. Bolegenova ◽  
V.Yu. Maximov ◽  
A.O. Nugymanova ◽  
...  
Keyword(s):  
Combustion Chamber ◽  
Mass Transfer Process ◽  
Fuel Combustion ◽  
Low Grade ◽  
Two Stage ◽  
Entire Volume ◽  
Coal Fuel ◽  
Air Supply ◽  
Stage Combustion ◽  
Combustion Technology

Studies have been carried out using numerical modeling methods to determine the effect of the introduction of a two-stage combustion technology (OFA technology) of high-ash Karaganda coal on the characteristics of combustion processes: aerodynamics of flows, temperature and concentration (COх, NOх) fields throughout the entire volume of the combustion chamber of the BKZ-75 boiler at Shakhtinskaya TPP and at the outlet from it. Comparison with the basic regime of combustion of pulverized coal fuel, when there is no air supply through additional injectors (OFA = 0%). To implement the technology of two-stage combustion, various regimes of additional air supply through injectors were chosen: OFA equals 0% (basic version, conventional combustion), 5%, 10%, 15%, 18%, 20%, 25% and 30% of total air volume required for fuel combustion. A comparative analysis of the main characteristics of the heat and mass transfer process in the combustion chamber for the investigated modes is carried out. It is shown that an increase in the volume of additional air supplied through the injectors up to 18% leads to a decrease in the concentration of nitrogen oxide NO by 25% in comparison with traditional combustion. A further increase in the volume of additional air leads to a deterioration in these indicators. The results obtained will make it possible to optimize the combustion of low-grade fuel in the combustion chamber of the BKZ-75 boiler, increase the efficiency of fuel burnout, reduce harmful emissions and introduce a two-stage combustion technology at other coal-fired TPPs.

scholarly journals Theoretical analysis of air-fuel mixture formation in the combustion chambers of the gas engine with two-stage combustion system

2014 ◽  
Vol 62 (4) ◽  
pp. 779-790 ◽  
Author(s):  
A. Jamrozik ◽  
W. Tutak
Keyword(s):  
Theoretical Analysis ◽  
Ignition Time ◽  
Combustible Mixture ◽  
Mixture Composition ◽  
Combustion System ◽  
Mixture Formation ◽  
Two Stage ◽  
Gas Engine ◽  
Compression Stroke ◽  
Stage Combustion

Abstract The results of theoretical analysis of a mixture formation process during the compression stroke in a prechamber of the IC (internal combustion) gas engine with the stratified mixtures two-stage combustion system were presented in the paper. The course of excess air-fuel ratio changes in prechamber at ignition time λkz in function of degree of the mixture condensation during the compression stroke φ expressing quotient of a temporary cylinder and prechamber volume and maximal value of the volume were estimated. Research concerning λkz sensitivity on changes of rich combustible mixture composition delivered to the prechamber by the additional fuel supply system λko, mixture composition in cylinder _c and degree of filling a prechamber with the rich combustible mixture ξ were performed. According to numerical calculations it was proved that the real gas engine with the two stage combustion system at equal degree requires exact regulation of the three analysed values.

CFD: Analysis of the Influence of Modified Tangential Air Inlets on the Combustion Behavior of a Two-Stage Combustion Chamber

2004 ◽  
Author(s):  
Klaus Hoerzer ◽  
Hermann Haselbacher
Keyword(s):  
Combustion Chamber ◽  
Flue Gas ◽  
Wood Dust ◽  
Parameter Study ◽  
Cfd Analysis ◽  
Two Stage ◽  
Combustion Performance ◽  
University Of Technology ◽  
Stage Combustion ◽  
Operation Parameters

At the Institute of Thermal Turbomachines and Powerplants at the Vienna University of Technology, a two-stage combustion chamber was designed and constructed to directly drive a gas turbine by combustion of wood dust. A commercial CFD-solver was applied to examine the effects of modifications of the geometry on the combustion performance. Since this parameter study was done with the same operation parameters and the same boundary conditions, the computational results represent the influence of the different flow fields caused by the modified combustion chamber. The particle gasification time, the temperature, and the chemical composition of the flue gas at the combustion chamber exit have been used for the assessment of the combustion performance.

USE OF TWO-STAGE FUEL COMBUSTION TECHNOLOGY TO MINIMIZE HAZARDOUS EMISSIONS AT KAZAKHSTAN TPP

2021 ◽  
Vol 335 (1) ◽  
pp. 74-80
Author(s):  
A.S. Askarova ◽  
P. Safarik ◽  
S.A. Bolegenova ◽  
V.Yu. Maximov ◽  
A.O. Nugymanova ◽  
...  
Keyword(s):  
Combustion Chamber ◽  
Mass Transfer Process ◽  
Fuel Combustion ◽  
Low Grade ◽  
Two Stage ◽  
Entire Volume ◽  
Coal Fuel ◽  
Air Supply ◽  
Stage Combustion ◽  
Combustion Technology

Studies have been carried out using numerical modeling methods to determine the effect of the introduction of a two-stage combustion technology (OFA technology) of high-ash Karaganda coal on the characteristics of combustion processes: aerodynamics of flows, temperature and concentration (COх, NOх) fields throughout the entire volume of the combustion chamber of the BKZ-75 boiler at Shakhtinskaya TPP and at the outlet from it. Comparison with the basic regime of combustion of pulverized coal fuel, when there is no air supply through additional injectors (OFA = 0%). To implement the technology of two-stage combustion, various regimes of additional air supply through injectors were chosen: OFA equals 0% (basic version, conventional combustion), 5%, 10%, 15%, 18%, 20%, 25% and 30% of total air volume required for fuel combustion. A comparative analysis of the main characteristics of the heat and mass transfer process in the combustion chamber for the investigated modes is carried out. It is shown that an increase in the volume of additional air supplied through the injectors up to 18% leads to a decrease in the concentration of nitrogen oxide NO by 25% in comparison with traditional combustion. A further increase in the volume of additional air leads to a deterioration in these indicators. The results obtained will make it possible to optimize the combustion of low-grade fuel in the combustion chamber of the BKZ-75 boiler, increase the efficiency of fuel burnout, reduce harmful emissions and introduce a two-stage combustion technology at other coal-fired TPPs.

Two-stage Combustion with Divided Combustion Chamber

2018 ◽  
Vol 2018 (0) ◽  
pp. J0710106
Author(s):  
Hiroshi SASAKI ◽  
Jun-ichi WADA ◽  
Nobuyuki SOMIYA
Keyword(s):  
Combustion Chamber ◽  
Two Stage ◽  
Stage Combustion

Effect of High Swirl Velocity on Mixture Formation and Combustion Process of Diesel Spray

2012 ◽  
Vol 229-231 ◽  
pp. 695-699 ◽  
Author(s):  
Amir Khalid ◽  
Bukhari Manshoor
Keyword(s):  
Combustion Chamber ◽  
High Speed ◽  
Combustion Process ◽  
Video Camera ◽  
Exhaust Emissions ◽  
Ignition Process ◽  
Mixture Formation ◽  
Digital Video Camera ◽  
Swirl Velocity ◽  
Flame Development

Diesel engines generate undesirable exhaust emissions during combustion process and identified as major source pollution in the worldwide ecosystem. To reduce emissions, the improvements throughout the premixing of fuel and air have been considered especially at early stage of ignition process. Purpose of this study is to clarify the effects of swirl velocity on flow fuel-air premixing mechanism and burning process in diesel combustion that strongly affects the exhaust emissions. The effects of physical factors on mixture formation and combustion process to improve exhaust emissions are discussed in detail. This study investigated diesel combustion fundamentally using a rapid compression machine (RCM) together with the schlieren photography and direct photography methods. RCM was used to simulate actual phenomenon inside the combustion chamber with changing design parameter such as swirl velocity, injection strategies and variable nozzle concept. The detail behavior of mixture formation during ignition delay period was investigated using the schlieren photography system with a high speed digital video camera. This method can capture spray evaporation, spray interference and mixture formation clearly with real images. Ignition process and flame development were investigated by direct photography method using a light sensitive high-speed color digital video camera. Moreover, the mechanism and behavior of mixture formation were analyzed by newly developed image analysis technique. Under high swirl condition, the ignition delay is extended, the higher heat losses and unutilized high-density oxygen associated with slower initial heat recovery begins might be the explanation for the longer combustion duration, reductions of pick heat release and promote combustion and soot oxidation. The real images of mixture formation and flame development reveal that the spray tip penetration is bended by the high swirl motion, fuel is mainly distributed at the center of combustion chamber, resulting that flame is only formed at the center region of the combustion chamber. It is necessary for high swirl condition to improve fuel-air premixing.

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