scholarly journals Numerical Model Analysis of Natural Gas Combustion Burners

2019 ◽  
Vol 4 (1) ◽  
pp. 67-71
Author(s):  
Amjd Ibraheem ◽  
Ferenc Szodrai
Keyword(s):  
Mass Flow ◽  
Power Plants ◽  
Experimental Testing ◽  
Input Parameter ◽  
Electrical Power ◽  
Fuel Mixture ◽  
Combustion Efficiency ◽  
Combustion Model ◽  
Ansys Fluent ◽  
Gas Combustion

Traditional power plants still the dominating power source for all the major industries and powerdemanding facilities, the most crucial facility for the whole plant operations is the industrial boiler which generatessteam, heating energy or electrical power. Boilers generate energy by combustion. The improvement of combustion efficiency could greatly influence the energy consumption and will make the boiler more efficient and cleaner (less emissions), that’s why it is important to understand the combustion and thermal flow behaviours inside the boiler. Beside experimental testing, computational work nowadays becoming more and more important due to lower cost and acceptable accuracy with minimum error. With numerical calculations method, the computational model created by a Computational Fluid Dynamics (CFD) software could reduce a lot of trial and error on experimental work. In this paper utilizing the ANSYS FLUENT 19.1 software to make crate the combustion model. The ratio of air to fuel mixture, the equivalency factor, mass flow rate of the mixture, velocity, mass fractions of the mixture components (fuel and air) and their temperatures will serve as the input parameter while the exhaust gase component mass fraction, temperature, mass flow and velocity will be monitored.

Combustion Simulation on Fuel Oil-Mixture Gas Converter Based on FLUENT

2012 ◽  
Vol 512-515 ◽  
pp. 1267-1272
Author(s):  
Jia Chao Yan ◽  
Shuai Shao ◽  
Cheng Zhe Jin
Keyword(s):  
Fuel Mixture ◽  
Thermal Recovery ◽  
Fuel Oil ◽  
Analysis Software ◽  
Ansys Fluent ◽  
Gas Combustion ◽  
Fuel Gas ◽  
Oil Exploitation ◽  
Combustion Simulation ◽  
Part Structure

Fuel oil-mixture gas converter is used for heavy oil exploitation is a new equipment of thermal recovery. Strength calculations and enthalpy values are related in the design. For selection and design to each part-structure of the fuel-mixture converter. Applied the analysis software of ANSYS FLUENT, fuel-gas combustion simulation is to combustion chamber of Fuel oil-mixture gas converter. The results show that the design is feasibility.

scholarly journals NUMERICAL ANALYSIS OF THE AIR-FUEL MIXTURE IN INDIRECT AND DIRECT INJECTION OF FOUR-STROKE ENGINES

2019 ◽  
Vol 18 (2) ◽  
pp. 89
Author(s):  
G. G. Narcizo ◽  
D. A. Miranda
Keyword(s):  
Internal Combustion Engines ◽  
Fuel Injection ◽  
Direct Injection ◽  
Fuel Mixture ◽  
Combustion Efficiency ◽  
Simulation Software ◽  
Injection System ◽  
Scholarly Work ◽  
Ansys Fluent ◽  
Dynamics Simulations

The quality of the air-fuel mixture in internal combustion engines directly affects the combustion efficiency, therefore a good design of the combustion chamber combined with the correct fuel injection system, can provide a better use of this mixture and increase the efficiency of the engine. Considering these aspects, this scholarly work presents a comparative study of the indirect injection system and direct fuel injection, analyzing the way the mixture behaves in these two conditions. For this, the Ansys Fluent simulation software was used, in which were applied computational fluid dynamics simulations of the air-fuel mixture. The objective of this scholarly work is to contribute to the development of the injection systems, enabling the improvement of new studies and developments of new nozzle models can be performed.

scholarly journals Numerical comparative analysis of the combustion process in an engine powered by CNG

2012 ◽  
Vol 148 (1) ◽  
pp. 62-70
Author(s):  
Ryszard MICHAŁOWSKI ◽  
Krzysztof MIKSIEWICZ ◽  
Marcin TKACZYK
Keyword(s):  
Fuel Injection ◽  
Combustion Process ◽  
Qualitative Evaluation ◽  
Fuel Mixture ◽  
Diesel Oil ◽  
Numerical Results ◽  
Combustion Model ◽  
Numerical Application ◽  
Gas Combustion ◽  
Natural Gas Combustion

This paper contains the analysis of Compressible Natural Gas combustion process in engine dedicated to diesel oil. The analysis was performed on the basis of the numerical results of two systems for methane dosing. The first simulation considers the CNG delivery into the suction manifold, and subsequent production of air-fuel mixture as well as separate combustion model of a homogenous mixture. The second simulation comprises a numerical application of the fuel injection directly into the combustion chamber. Therefore it is also a simulation of a combustion process. Among the numerical results conducted with the aid of Computational Fluid Dynamics the following parameters were selected for the combustion qualitative evaluation in terms of mechanical, heat and flow properties: fields of pressure and temperature, mass fraction of the fuel and turbulence intensity. All test were conducted on the engine adopted to be fed with CNG.

scholarly journals Performance assessment of solar chimney power plants with the impacts of divergent and convergent chimney geometry

2021 ◽  
Author(s):  
Erdem Cuce ◽  
Abhishek Saxena ◽  
Pinar Mert Cuce ◽  
Harun Sen ◽  
Shaopeng Guo ◽  
...  
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Power Plants ◽  
Dynamic Pressure ◽  
Electrical Power ◽  
Independent Solution ◽  
System Efficiency ◽  
Solar Chimney ◽  
Reference Case

Abstract Influence of area ratio (AR) on main performance parameters of solar chimney power plants (SCPPs) is investigated through a justified 3D axisymmetric CFD model. Geometric characteristics of Manzanares pilot plant (MPP) are taken into consideration for the numerical model. AR is varied from 0.5 to 10 to cover both concave and convex (convergent and divergent) solar chimney designs. Following the accuracy verification of the CFD results and proving mesh-independent solution, main performance oriented parameters are assessed as a function of AR such as velocity, temperature and pressure distribution within MPP, temperature rise of air in collector, mass flow rate of air around the turbine area, dynamic pressure difference across the turbine, minimum static pressure in the entire plant, power output and system efficiency. The results reveal that AR plays a vital role in performance figures of MPP. Mass flow rate of air ($\dot{m}$) is found to be 1122.1 kg/s for the reference geometry (AR = 1), whereas it is 1629.1 kg/s for the optimum AR value of 4. System efficiency (η) is determined to be 0.29% for the reference case; however, it is enhanced to 0.83% for the AR of 4.1. MPP can generate 54.3 kW electrical power in its current design while it is possible to improve this figure to 168.5 kW with the optimal AR value.

Experimental Study on Low Load Operation Range Extension by Autothermal On-Board Syngas Generation

2018 ◽  
Author(s):  
Max H. Baumgärtner ◽  
Thomas Sattelmayer
Keyword(s):  
Natural Gas ◽  
Mass Flow ◽  
Power Output ◽  
Gas Turbines ◽  
Power Plants ◽  
Combined Cycle ◽  
Nox Emissions ◽  
Gas Combustion ◽  
Low Load ◽  
Natural Gas Combustion

Volatile renewable energy sources induce power supply fluctuations. These need to be compensated by flexible conventional power plants. Gas turbines in combined cycle power plants adjust the power output quickly but their turn-down ratio is limited by the slow reaction kinetics which lead to CO and unburned hydrocarbon (UHC) emissions. To extend the turn-down ratio, part of the fuel can be converted to syngas, which exhibits a higher reactivity. By an increasing fraction of syngas in the fuel, the reactivity of the mixture is increased and total fuel mass-flow and the power output can be reduced. An Autothermal On-board Syngas Generator in combination with two different burner concepts for natural gas/syngas mixtures was presented in a previous study [1]. The study at hand shows a mass-flow variation of the reforming process with mass-flows which allow for pure syngas combustion and further improvements of the two burner concepts which result in a more application-oriented operation. The first of the two burner concepts comprises a generic swirl stage with a central lance for syngas injection. Syngas is injected with swirl to avoid a negative impact on the total swirl intensity and non-swirled. The second concept includes a central swirl stage with an outer ring of jets. For this burner, syngas is injected in both stages to avoid NOx emissions from the swirl stage. Increased NOx emissions produced by natural gas combustion of the swirl pilot was reported in last year’s paper. For both burners, combustion performance is analyzed by OH*-chemiluminescence and gaseous emissions. The lowest possible adiabatic flame temperature without a significant increase of CO emissions was 170 K – 210 K lower for the syngas compared to low load pure natural gas combustion. This corresponds to a decrease of 15–20 % in terms of thermal power.

Optical and thermodynamic investigations of a methane and hydrogen blend fueled large bore engine

2022 ◽  
pp. 146808742110667
Author(s):  
Stephan Karmann ◽  
Stefan Eicheldinger ◽  
Maximilian Prager ◽  
Georg Wachtmeister
Keyword(s):  
Natural Gas ◽  
Power Plants ◽  
Equivalence Ratio ◽  
Fuel Mixture ◽  
Green Energy ◽  
Optical Investigation ◽  
Oh Radical ◽  
Gas Combustion ◽  
Complete Combustion ◽  
Fuel Blends

The following paper presents thermodynamic and optical investigations of the natural flame and OH radical chemiluminescence of a hydrogen enriched methane combustion compared to natural gas combustion. The engine under investigation is a port-fueled unscavenged prechamber 4.8 L single cylinder large bore engine. The blends under consideration are 2%V, 5%V,10%V, and 40%V of hydrogen expected to be blended within existing natural gas grids in a short and mid-term timeline in order to store green energy from solar and wind. These fuel blends could be used for stabilization of the energy supply by reconverting the renewable fuel CH4/H2 in combined heat and power plants. As expected, admixture of hydrogen extends the ignition limits of the fuel mixture toward lean ranges up to an air-fuel equivalence ratio of almost 2. No negative effect on combustion is observed up to an admixture of 40%V hydrogen. At 40%V hydrogen, abnormal combustion like backfire occurs at an air-fuel equivalence ratio of 1.5. The higher mixtures exhibit increased nitrogen oxide emissions due to higher combustion chamber temperatures, while methane slip and CO emissions are reduced due to more complete combustion. The optical investigation of the natural flame and OH radical chemiluminescence are in good agreement with the thermodynamic results verifying the more intense combustion of the fuel blends by means of the chemiluminescence intensity. Further, lube oil combustion and a continuing luminescence after the thermodynamic end of combustion are observed.

Effect of Chemical Hythane Composition on Pressure in Combustion Chamber of Engine

2019 ◽  
pp. 36-42
Author(s):  
A. P. Shaikin ◽  
I. R. Galiev
Keyword(s):  
Natural Gas ◽  
Combustion Chamber ◽  
Power Plants ◽  
Engine Speed ◽  
Combustion Engine ◽  
Fuel Mixture ◽  
Maximum Pressure ◽  
Chamber Volume ◽  
Excess Air ◽  
Scientific Papers

The article analyzes the influence of chemical composition of hythane (a mixture of natural gas with hydrogen) on pressure in an engine combustion chamber. A review of the literature has showed the relevance of using hythane in transport energy industry, and also revealed a number of scientific papers devoted to studying the effect of hythane on environmental and traction-dynamic characteristics of the engine. We have studied a single-cylinder spark-ignited internal combustion engine. In the experiments, the varying factors are: engine speed (600 and 900 min-1), excess air ratio and hydrogen concentration in natural gas which are 29, 47 and 58% (volume).The article shows that at idling engine speed maximum pressure in combustion chamber depends on excess air ratio and proportion hydrogen in the air-fuel mixture – the poorer air-fuel mixture and greater addition of hydrogen is, the more intense pressure increases. The positive effect of hydrogen on pressure is explained by the fact that addition of hydrogen contributes to increase in heat of combustion fuel and rate propagation of the flame. As a result, during combustion, more heat is released, and the fuel itself burns in a smaller volume. Thus, the addition of hydrogen can ensure stable combustion of a lean air-fuel mixture without loss of engine power. Moreover, the article shows that, despite the change in engine speed, addition of hydrogen, excess air ratio, type of fuel (natural gas and gasoline), there is a power-law dependence of the maximum pressure in engine cylinder on combustion chamber volume. Processing and analysis of the results of the foreign and domestic researchers have showed that patterns we discovered are applicable to engines of different designs, operating at different speeds and using different hydrocarbon fuels. The results research presented allow us to reduce the time and material costs when creating new power plants using hythane and meeting modern requirements for power, economy and toxicity.

scholarly journals Combustion Optimization for Coal Fired Power Plant Boilers Based on Improved Distributed ELM and Distributed PSO

Energies ◽  
2019 ◽  
Vol 12 (6) ◽  
pp. 1036 ◽  
Author(s):  
Xinying Xu ◽  
Qi Chen ◽  
Mifeng Ren ◽  
Lan Cheng ◽  
Jun Xie
Keyword(s):  
Power Plant ◽  
Combustion Process ◽  
Optimization Method ◽  
Combustion Efficiency ◽  
Pollutant Emissions ◽  
Combustion Model ◽  
Nox Emissions ◽  
Coupling Characteristics ◽  
Learning Machine ◽  
Combustion Optimization

Increasing the combustion efficiency of power plant boilers and reducing pollutant emissions are important for energy conservation and environmental protection. The power plant boiler combustion process is a complex multi-input/multi-output system, with a high degree of nonlinearity and strong coupling characteristics. It is necessary to optimize the boiler combustion model by means of artificial intelligence methods. However, the traditional intelligent algorithms cannot deal effectively with the massive and high dimensional power station data. In this paper, a distributed combustion optimization method for boilers is proposed. The MapReduce programming framework is used to parallelize the proposed algorithm model and improve its ability to deal with big data. An improved distributed extreme learning machine is used to establish the combustion system model aiming at boiler combustion efficiency and NOx emission. The distributed particle swarm optimization algorithm based on MapReduce is used to optimize the input parameters of boiler combustion model, and weighted coefficient method is used to solve the multi-objective optimization problem (boiler combustion efficiency and NOx emissions). According to the experimental analysis, the results show that the method can optimize the boiler combustion efficiency and NOx emissions by combining different weight coefficients as needed.

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