scholarly journals SIMULATION OF BIOGAS COMBUSTION IN INJECTION BURNER WITH HEAT DIVIDER

2020 ◽  
pp. 40-47
Author(s):  
D. Suslov ◽  
R. Ramazanov
Keyword(s):  
Software Package ◽  
Flame Temperature ◽  
Combustion Process ◽  
Methane Content ◽  
Ansys Fluent ◽  
Preliminary Heating ◽  
Injection Burner ◽  
Modeling Software

The purpose of this work is to develop a design of a biogas combustion equipped with a thermal divider and study the process of burning biogas of different composition. To study the biogas combustion process in the burner of the developed design, the Ansys Fluent modeling software package is used. An injection burner for biogas combustion with a cone-shaped thermal divider and primary air regulator has been developed. Studies of the process of burning biogas of different composition in burners of 5 designs were carried out: without a divider, with a divider with a length of L = 6 mm, with a divider L = 12 mm, with a divider L = 18 mm and a divider L = 24 mm. As a result of modeling, it is found that the placement of a divider with a length of 6 mm and 12 mm does not affect the temperature of the gas-air mixture in the burner body. Increasing the length of the divider to 18 mm allows to increase the temperature of the flow of the gas-air mixture passing along the divider. A further increase in the length of the divider to 24 mm leads to a slight increase in the temperature of the gas-air mixture. The dependences of the flame temperature on the length of the divider during the combustion of biogas with a methane content of 60% and 70% are obtained. When a divider with a length of 6 mm and 12 mm is placed in the burner body, the flame temperature decreases, with an increase in the length of the divider to 18 mm, the flame temperature increases, and with an increase in the length of the divider to 24 mm, the flame temperature remains practically unchanged. Consequently, the placement of a divider with a length of 18 ... 24 mm in the burner body ensures preliminary heating of the gas-air mixture and allows increasing the efficiency of the biogas combustion process.

scholarly journals RESEARCH OF INFLUENCE OF AIR TEMPERATURE ON THE LEVEL OF NITROGEN OXIDES IN SMOKE GASES OF BOILER PLANTS

2019 ◽  
Vol 9 (4) ◽  
pp. 27-32
Author(s):  
Olga A. BALANDINA ◽  
Svetlana M. PURING
Keyword(s):  
Mathematical Modeling ◽  
Nitric Oxide ◽  
Nitrogen Oxides ◽  
Flue Gas ◽  
Software Package ◽  
Flame Temperature ◽  
Combustion Process ◽  
Flue Gases ◽  
Oxidizing Agent ◽  
Mixture Formation

The analysis of the values of the concentrations of the formed nitrogen oxides and the temperatures of the jet plume under various conditions of mixture formation is carried out. The plots of the distribution of torch temperatures and concentrations of nitric oxide in the calculated area for oxidizer temperatures of 20, 60, 100, 150, and 200 ° C were obtained and analyzed. Mathematical modeling of the gaseous fuel combustion process was carried out using the FlowVision software package. An analysis of the results showed that a decrease in the temperature of the air supplied as an oxidizing agent leads to a significant decrease in the concentration of nitrogen oxides in flue gases, while not significantly affecting the change in the flame temperature. The research results can be used to solve the problems of optimizing boiler plants, in order to reduce harmful flue gas emissions. Further modeling is planned to determine the dependence of the influence of various factors on the degree of formation of nitrogen oxides in the flue gases of boiler plants.

Experimental and Numerical Analysis of a Motorcycle Air Intake System Aerodynamics and Performance

2020 ◽  
Vol 17 (1) ◽  
Author(s):  
M. A. Abd Halim ◽  
N. A. R. Nik Mohd ◽  
M. N. Mohd Nasir ◽  
M. N. Dahalan
Keyword(s):  
Combustion Process ◽  
Three Dimensional ◽  
Engine Performance ◽  
Internal Flow ◽  
Rapid Expansion ◽  
Navier Stokes ◽  
Turbulent Fluctuation ◽  
Ansys Fluent ◽  
Induction System ◽  
Acceleration And Deceleration

Induction system or also known as the breathing system is a sub-component of the internal combustion system that supplies clean air for the combustion process. A good design of the induction system would be able to supply the air with adequate pressure, temperature and density for the combustion process to optimizing the engine performance. The induction system has an internal flow problem with a geometry that has rapid expansion or diverging and converging sections that may lead to sudden acceleration and deceleration of flow, flow separation and cause excessive turbulent fluctuation in the system. The aerodynamic performance of these induction systems influences the pressure drop effect and thus the engine performance. Therefore, in this work, the aerodynamics of motorcycle induction systems is to be investigated for a range of Cubic Feet per Minute (CFM). A three-dimensional simulation of the flow inside a generic 4-stroke motorcycle airbox were done using Reynolds-Averaged Navier Stokes (RANS) Computational Fluid Dynamics (CFD) solver in ANSYS Fluent version 11. The simulation results are validated by an experimental study performed using a flow bench. The study shows that the difference of the validation is 1.54% in average at the total pressure outlet. A potential improvement to the system have been observed and can be done to suit motorsports applications.

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.

scholarly journals Solution of the conjugate problem of gas dynamics and heat transfer in structures with a large ratio of geometric scale values

2017 ◽  
pp. 69-74
Author(s):  
D. A. Romanyuk ◽  
S. V. Panfilov ◽  
D. S. Gromov
Keyword(s):  
Gas Dynamics ◽  
Software Package ◽  
Thermal State ◽  
Mathematical Formulation ◽  
Research Work ◽  
Conjugate Problem ◽  
Thermal Processes ◽  
Ansys Fluent ◽  
Fluent Software ◽  
Volume Method

Within the scope of the research work, we have developed the methods and software package for solving the conjugate heat and hydraulic problems based on the classical approach to performing hydraulic calculations and modeling thermal processes by means of the finite volume method in the ANSYS Fluent software package. The developed means allowed us to efficiently calculate the thermal state of complex technical objects. The study gives mathematical formulation of the methods and suggests the results of their approbation and verification

scholarly journals Modelling of hydrodynamic cavitation for treatment of wastewater in a Venturi tube

2020 ◽  
Vol 14 (1) ◽  
pp. 61-66
Author(s):  
Betti Bolló
Keyword(s):  
Software Package ◽  
Venturi Tube ◽  
Hydrodynamic Cavitation ◽  
Ansys Fluent ◽  
High Effectiveness ◽  
Commercial Software Package ◽  
Promising Application ◽  
Low Costs ◽  
Modern Technologies ◽  
Degradation Of Pollutants

Treatment of municipal effluents has long been a challenge for modern technologies combining high effectiveness of degradation of pollutants with low costs of the process. Hydrodynamic cavitation is a promising application in wastewater treatment due to its simple reactor design. In this work, for a system available in the laboratory a hydrodynamic reactor is designed based on literature recommendations. On the designed Venturi tube, two-dimensional numerical simulations were investigated by the means of CFD computations using the commercial software package, Ansys Fluent. The resulting cavitation bubbles were analysed at different inlet pressures.

scholarly journals Combustion of Fuel Surrogates: An Application to Gas Turbine Engines

2021 ◽  
Author(s):  
Mansour Al Qubeissi ◽  
Nawar Al-Esawi ◽  
Hakan Serhad Soyhan
Keyword(s):  
Gas Turbine ◽  
Combustion Process ◽  
Chemical Mechanism ◽  
Cfd Modelling ◽  
Ansys Fluent ◽  
Turbine Engine ◽  
Fuel Blends ◽  
Combustion Simulation ◽  
Fuel Surrogate ◽  
Fuel Surrogates

The previously developed models for fuel droplet heating and evaporation processes, mainly the Discrete Multi Component Model (DMCM), and Multi-Dimensional Quasi-Discrete Model (MDQDM) are investigated for the aerodynamic combustion simulation. The models have been recently improved, and generalised for a broad range of bio-fossil fuel blends so that the application areas are broadened with increased accuracy. The main distinctive features of these models are that they consider the impacts of species thermal conductivities and diffusivities within the droplets to account for the temperature gradient, transient diffusion of species and recirculation. A formulation of fuel surrogates is made, using the recently introduced model, referred to as ‘’Complex Fuel Surrogate Model (CFSM)’’ and analysing their heating, evaporation, and combustion characteristics. The CFSM is aimed to reduce the full composition of fuel to a much smaller number of components based on their mass fractions, and to formulate fuel surrogates. Such approach has provided a proof of concept with the implementation of the developed model into a commercial CFD code ANSYS-Fluent. A case study is made for the CFD modelling of gas-turbine engine using kerosene fuel surrogate. The surrogate is proposed using the CFSM. The model is implemented into ANSYS-Fluent via a user-defined function to provide the first full simulation of the combustion process. Detailed chemical mechanism is also implemented into ANSYS Chemkin for the combustion study.

scholarly journals Chemiluminescence analysis of the effect of butanol-diesel fuel blends on the spray-combustion process in an experimental common rail diesel engine

2015 ◽  
Vol 19 (6) ◽  
pp. 1943-1957
Author(s):  
Simona Merola ◽  
Luca Marchitto ◽  
Cinzia Tornatore ◽  
Gerardo Valentino
Keyword(s):  
Diesel Fuel ◽  
Flame Temperature ◽  
Combustion Process ◽  
Injection Pressure ◽  
Common Rail ◽  
Pilot Injection ◽  
Soot Emission ◽  
Compression Ignition Engine ◽  
Working Cycle ◽  
Main Injection

Combustion process was studied from the injection until the late combustion phase in an high swirl optically accessible combustion bowl connected to a single cylinder 2-stroke high pressure common rail compression ignition engine. Commercial diesel and blends of diesel and n-butanol (20%: BU20 and 40%: BU40) were used for the experiments. A pilot plus main injection strategy was investigated fixing the injection pressure and fuel mass injected per stroke. Two main injection timings and different pilot-main dwell times were explored achieving for any strategy a mixing controlled combustion. Advancing the main injection start, an increase in net engine working cycle (>40%) together with a strong smoke number decrease (>80%) and NOx concentration increase (@50%) were measured for all pilot injection timings. Compared to diesel fuel, butanol induced a decrease in soot emission and an increase in net engine working area when butanol ratio increased in the blend. A noticeable increase in NOx was detected at the exhaust for BU40 with a slight effect of the dwell-time. Spectroscopic investigations confirmed the delayed auto-ignition (~60 ms) of the pilot injection for BU40 compared to diesel. The spectral features for the different fuels were comparable at the start of combustion process, but they evolved in different ways. Broadband signal caused by soot emission, was lower for BU40 than diesel. Different balance of the bands at 309 and 282 nm, due to different OH transitions, were detected between the two fuels. The ratio of these intensities was used to follow flame temperature evolution.

scholarly journals A Thermodynamic Analysis of an Air-Cooled Proton Exchange Membrane Fuel Cell Operated in Different Climate Regions

Energies ◽  
2020 ◽  
Vol 13 (10) ◽  
pp. 2611 ◽  
Author(s):  
Torsten Berning ◽  
Søren Knudsen Kær
Keyword(s):  
Fuel Cell ◽  
Thermodynamic Analysis ◽  
Operating Temperature ◽  
Flame Temperature ◽  
Combustion Process ◽  
Cell Voltage ◽  
Proton Exchange ◽  
Outlet Temperature ◽  
Flow Ratio ◽  
Ambient Conditions

A fundamental thermodynamic analysis of an air-cooled fuel cell, where the reactant air stream is also the coolant stream, is presented. The adiabatic cell temperature of such a fuel cell is calculated in a similar way as the adiabatic flame temperature in a combustion process. Diagrams that show the dependency of the cathode outlet temperature, the stoichiometric flow ratio and the operating cell voltage are developed. These diagrams can help fuel cell manufacturers to identify a suitable blower and a suitable operating regime for their fuel cell stacks. It is found that for standard conditions, reasonable cell temperatures are obtained for cathode stoichiometric flow ratios of ξ = 50 and higher, which is in very good agreement with manufacturer’s recommendations. Under very cold ambient conditions, the suggested stoichiometric flow ratio is only in the range of ξ = 20 in order to obtain a useful fuel cell operating temperature. The outside relative humidity only plays a role at ambient temperatures above 40 °C, and the predicted stoichiometric flow ratios should be above ξ = 70 in this region. From a thermodynamic perspective, it is suggested that the adiabatic outlet temperature is a suitable definition of the fuel cell operating temperature.

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