Gas Temperature Distribution Research Articles

A simulation model for ruthenium-catalyzed dry reforming of methane (DRM) at different temperatures and gas compositions

Dry reforming of methane (DRM) is an environmentally friendly technology for producing syngas while consuming CO2. However, the short lifespan of catalysts due to metal sintering, coke deposition, and sulfur poisoning hinders its widespread adoption. To address such issues, perovskite catalysts, which have shown superior performance and resistance to coke formation and poisoning, were developed. In this study, a comprehensive simulation model of a DRM reactor that employs Sr0·92Y0·08Ti0·95Ru0·05O3-d (SYTRu5) using COMSOL Multiphysics software was developed. The objective of this study is to contribute to the understanding of the intricate dynamics of DRM process via utilizing simulation models. The simulation model considered five main reactions and calculated the properties of the gas mixture considering temperatures and compositions. Using the simulation model, the distribution of gas mole fractions and temperatures were obtained. According to the results, the H2 yield and CO2 conversion rate increased with increasing operating temperature. The temperature of the catalyst bed decreased rapidly owing to the endothermicity of the reaction. Additionally, the CH4 conversion rate increased with increasing proportion of CO2, whereas the reaction converged to an equilibrium state and the temperature difference in the catalyst bed decreased with decreasing gas flow rate.

Effect of the swirl angle on calcium carbide gas combustion characteristics of lower burner under annular shaft kiln

In order to solve the problem of high CO concentration in the emitted flue gas after adopting the flue gas recirculation technology in the annular shaft kiln, in this paper, the combustion characteristics of calcium carbide gas in swirl burners under the annular shaft kilns were studied by numerical simulation, the influence of fuel and primary air swirl intensity on combustion characteristics were studied, and the gas temperature distribution, pressure distribution and combustion products including CO, CO2 and NO was analyzed. The results show that the fuel gas swirl intensity has a great influence on the improvement of fuel burn-out ratio. The angle of the fuel gas blade increases, the maximum temperature of the combustion flame and the fuel combustion rate increase, and the CO content at the outlet of the burner decreases. When the angle of the fuel gas blade increased from 30o to 55o, swirl number increased from 0.41 to 1.02, the CO content at the inner sleeve position decreased from 8929 mg/m3 to 2467 mg/m3. The results also show that the effect of the primary air swirl intensity on reduce CO emissions and NOx formation was not obvious.

Two-dimensional modeling of diamond growth by microwave plasma activated chemical vapor deposition: Effects of pressure, absorbed power and the beneficial role of nitrogen on diamond growth

A two-dimensional (2D(r, z)) self-consistent model developed and validated in previous studies of diamond deposition processes in microwave (MW) plasma activated chemical vapor deposition reactors is applied in a systematic study of ways in which the gas pressure (over the range p = 75–350 Torr) and absorbed power (P = 1–3 kW) affect the plasma parameters, species distributions and diamond deposition processes from a gas mixture (1%CH4/H2 with 60 ppm added N2) at substrate temperatures (Ts = 1073 and 1323 K) and diameters (ds = 32–100 mm). A more limited set of process conditions for a 0.006%N2/4%CH4/H2 gas mixture and Ts = 1038–1153 K are investigated also. The study traces variations in the global distributions of electron concentration, electron and gas temperature, absorbed power density, key species concentrations and the hydrocarbon interconversion reactions, with particular focus on the radial profiles of CH3 radical and H atom concentrations just above the substrate and on predicted diamond growth rates, G(r). The results and the trends revealed when varying p and P should help guide future optimizations of deposition regimes. The absorbed power density is shown to exhibit quite steep gradients in both the radial (r) and axial (z) directions. This, and the finding of significant power absorption beyond the glowing plasma region, limits the utility of the oft-quoted ‘averaged power density’ as a parameter. The modeling also highlights the essential 2D character of the hydrocarbon interconversion and diffusion transfer processes, which challenges the applicability of any 1D modeling of such MW plasmas. Trace additions of N2 to a MW plasma activated CH4/H2 gas mixture have negligible effect on the plasma parameters or chemistry yet are known to boost the diamond growth rate. A semi-empirical expression for G(r) is developed further to explicitly include the effects of added N2 and a new mechanistic picture presented to account for the observed N-induced enhancements in G. This picture invokes stable moieties such as that formed by CH2 insertion into a CN dimer bond on the 2 × 1 reconstructed (100) diamond surface as ‘anchor’ sites that enable shorter CH2 surface migration lengths and more step-edges for irreversible incorporation of such migrating groups on the growing diamond surface.

Numerical analysis of SO2 removal characteristics in industrial flue gas desulfurization reactor by spray drying adsorption

The flue gas desulfurization reactor by spray drying adsorption plays a crucial role in the process of gas purification. This study employed the multi-phase particle-in-cell method to accurately model the three-dimensional motion of particles of different sizes in the flue gas desulfurization reactor. The double-film theory was utilized to simulate the heat and mass transfer processes of desulfurization slurry droplets. Additionally, this study conducted a comprehensive analysis of various factors affecting gas-solid flow and mass transfer processes, including flue gas inlet velocity and temperature, Ca/S molar ratio, slurry particle size, and slurry temperature. The results demonstrate that the simulated and experimental results are in good agreement, validating the reliability of the developed model. The axial mass fluxes of gas and particles exhibit contrasting distributions in the central part and near the wall, with the turbulent viscosity being particularly pronounced in the top nozzle region. The inlet velocity of flue gas has a limited effect on the axial mass flux of particles, whereas the Ca/S molar ratio exerts a more significant influence. Furthermore, the Ca/S molar ratio has a substantial impact on the spatial distribution of flue gas temperature. The inlet velocity of flue gas and slurry particle size are negatively and positively correlated with particle residence time, respectively. Based on the mass transfer characteristics, the reactor interior can be divided into three zones: a high-efficiency desulfurization zone, a low-efficiency desulfurization zone, and a partial desulfurization zone. For the investigated operating conditions, the desulfurization efficiency is most strongly influenced by the slurry particle size, followed by the flue gas inlet velocity, Ca/S molar ratio, flue gas inlet temperature, and slurry temperature.

Nongrowth regime in microwave chemical vapor deposition reactor due to formation of plasma nonhomogeneity

AbstractA new form of microwave discharge with a filament inside plasma volume was investigated in a microwave plasma‐assisted chemical vapor deposition (CVD) reactor. The threshold values of methane content in a hydrogen–methane gas mixture, gas pressure, and microwave power for discharge transition to the new form were found. The parameters' range of existence of the new form of discharge was investigated in three types of CVD reactors. Measurements of the electron density, gas temperature, and spatial distributions of the plasma optical emission lines intensity were carried out for both forms of the discharge. The reasons for the transition of the discharge to a new form and the possibility of using the new discharge form in the microwave plasma‐assisted (MPA) CVD reactor are discussed.

An experimental study on gas temperature characteristic in tunnel fires: The influences of sidewall restriction and sealing effect

This work provides a comprehensive experimental study on the influence of fire source position on gas temperature characteristics during the sealing process. A function correlating the ceiling maximum gas temperature and transverse fire source position factor and the sealing ratio was proposed based on theoretical analysis. Then, a series of methanol pool fire experiments were conducted in a reduced tunnel, considering three fire source positions and five sealing ratios, to investigate the influence of sidewall restriction and sealing effect on the maximum gas temperature and longitudinal distribution pattern. The results demonstrate that the maximum gas temperature does not increase continuously as the fire source moves toward the sidewall. There exists a position in which the lowest gas temperature beneath the ceiling is generated as a result of the combined effect of the flame on air entrainment and the enhanced radiation of the flame to the sidewall. Moreover, the maximum gas temperature rise is found to linearly increase with the sealing ratio and vary as a quadratic function of the transverse fire source position factor. Finally, the calculation model for the longitudinal distribution pattern of ceiling gas temperature rise is developed, which can provide reasonable predictions for different fire scenarios considering fire locations, sealing ratios as well as fire sizes.

Experimental characterization of TIAGO torch discharges: surface wave discharge behavior and (post-)discharge kinetics

The Torche à Injection Axial sur Guide d’Ondes source—better-known as the TIAGO torch—is a particular type of microwave-induced plasma that has become a focus of technological and scientific interest due to its outstanding features. Moreover, the TIAGO torch device arouses interest thanks to its remarkable performance in many challenging areas, such as green energy generation and graphene production by hydrocarbon decomposition. Although it has not been experimentally demonstrated to date, discharges generated by a TIAGO torch have been theoretically predicted to be surface wave discharges (SWDs), a kind of plasma leading the development of new materials. Therefore, deeper and fundamental research on this device is needed to optimize the implementation of plasma technology in these fields. In this study, the axial distribution of gas temperature, electron density and intensity of the main atomic and molecular emissions have been studied by optical emission spectroscopy when feeding the discharge with different input power values (200, 400 and 600 W). A complete axial characterization of both the dart and the plume regions is depicted and, according to the data obtained for the main plasma parameters, different regions can be identified, with the radiation zone being reported for the first time at atmospheric pressure. The kinetics of both the dart and the plume are discussed and an experimental verification of TIAGO torch behavior as a SWD is presented for the first time.

Conductive heat transfer through nanoconfined argon gas: From continuum to free-molecular regime

Heat transfer across nanogaps between solid surfaces has received an increased attention driven by both recent experimental investigations and technological applications as well. Most of the studies concerned, however, vacuum conditions and relatively few attention has been paid to the situation where a gas occupied the gap. This latter situation is difficult to handle theoretically because a continuum description of heat transfer across a nanoconfined gas medium completely breaks down. This breakdown maybe related not only to the partially ballistic nature of heat transfer between the surfaces but also to the existence of an adsorbed gas layer which affects energy transfer across the gap. In this work, to better understand the interplay of these effects, we present a series of molecular dynamics simulations of argon gas confined between either metallic or silicon walls held at different temperatures. The gas density is tuned so that the gas experiences a wide range of Knudsen numbers ranging from the continuum to the free molecular regime. It is shown that the Debye temperature of the solid controls the amount of adsorbed gas close to the walls, which in turn controls heat conduction in the middle of the channel. While the nanochannel walls significantly impact the density and temperature distributions of the rarefied gas, the pressure and the heat flux across the gas domain converge toward a plateau as the gas becomes denser. Finally, we also derive new analytical formulas to calculate the gas pressure, induced heat flux, and effective thermal conductivity of the nanoconfined gas. These formulae, which take into account the effects of an adsorbed gas layer, are shown to hold over a broad range of Knudsen numbers in the range 0.05–20. This framework allows one to predict nanoscale heat transfer across a gas confined by a variety of solid walls.

Analysis of the thermophysical process within the SEOP polarized 3He system

Temperature is a crucial parameter in the spin-exchange optical pumping (SEOP) process of noble gas (3He), but is hard to measure due to its confinement nature. In this paper, we conduct research upon the temperature and gas flow distribution within a sealed SEOP cell through computational fluid dynamics simulation. The simulation result shows that the external heat exchange of the initial heating of the cell becomes a cooling process in the presence of high pumping laser power absorbed by the alkali metal. The heat from the pumping laser would also cause the gas in the cell to reach a much higher temperature than the oven, with the hottest part appearing on the upper side of the cell. These predicted behaviors from the simulation are later confirmed by our experiment measurement, which strongly indicates that a gas flow and heat flow exist within the cell. These results help us to understand the temperature distribution of 3He gas in the cell and provide references for the development and improvement of the future SEOP system.

Mapping Protoplanetary Disk Vertical Structure with CO Isotopologue Line Emission

High-spatial-resolution observations of CO isotopologue line emission in protoplanetary disks at mid-inclinations (≈30°–75°) allow us to characterize the gas structure in detail, including radial and vertical substructures, emission surface heights and their dependencies on source characteristics, and disk temperature profiles. By combining observations of a suite of CO isotopologues, we can map the two-dimensional (r, z) disk structure from the disk upper atmosphere, as traced by CO, to near the midplane, as probed by less abundant isotopologues. Here, we present high-angular-resolution (≲0.″1 to ≈0.″2; ≈15–30 au) observations of CO, 13CO, and C18O in either or both J = 2–1 and J = 3–2 lines in the transition disks around DM Tau, Sz 91, LkCa 15, and HD 34282. We derived line emission surfaces in CO for all disks and in 13CO for the DM Tau and LkCa 15 disks. With these observations, we do not resolve the vertical structure of C18O in any disk, which is instead consistent with C18O emission originating from the midplane. Both the J = 2–1 and J = 3–2 lines show similar heights. Using the derived emission surfaces, we computed radial and vertical gas temperature distributions for each disk, including empirical temperature models for the DM Tau and LkCa 15 disks. After combining our sample with literature sources, we find that 13CO line emitting heights are also tentatively linked with source characteristics, e.g., stellar host mass, gas temperature, disk size, and show steeper trends than seen in CO emission surfaces.

Experimental study on vertical temperature distribution of the two-layer smoke flow in tunnel during construction

For a tunnel fire during construction, the formation of two-layer smoke flow underneath the ceiling accelerates the smoke descent threatening the personnel evacuation. As an important indicator of smoke diffusion, the gas temperature distribution inside tunnel is worthy of analysis in depth. However, the vertical temperature profiles within this kind of two-layer smoke flow inside tunnel have not been experimentally studied. To fill the gap, this paper conducts a series of fire experiments in a 1/20 reduced-scale tunnel model. Multi-variables including fire heat release rate, fire position, lifting-up height of fire source, inclined shaft slope, are considered. The visible flame shape, O2 volume fraction and gas temperature are recorded and measured. The burning of the propane gas persists steadily for 20 mins without the occurrence of self-extinction. The structural evolutions of the smoke layer are predicted by FDS simulation and traced by the laser sheet. The smoke descent process in the main tunnel is divided into three stages. The effects of fire source position, inclined shaft slope, fire heat release rate and lifting-up height on the gas temperature distributions inside tunnel are analyzed. The measured temperature rise and the perpendicular distance from the ceiling are normalized by ΔTmax and LT, respectively. At various longitudinal positions (1.82 ≤ │X-dm│/Hef ≤ 10.68), the normalized temperature distributions follow the same curve, independent of the values of Qm, dm and hm. The self-similarity of the vertical temperature distribution within the two-layer smoke flow are sufficiently proved. It is found that ΔT/ΔTmax with z/LT shows a two-regional variation. Based on over 1,740 temperature data from 36 experimental cases, an experimental equation is proposed to describe the gas temperature rise in the region between the fire source and the closed end. The proposed model shows good agreement with the measured data, which can help the researchers to better assess the smoke layer height inside tunnel.

Numerical simulation on gas-droplet flow characteristics and spray evaporation process in CFB-FGD tower

Nozzle arrangement in the nozzle spray system has a significant impact on the gas-droplet flow characteristics and the temperature distribution within the circulating fluidized bed flue gas desulphurization (CFB-FGD) tower, which is critical to the SO2 removal efficiency. The effects of spray direction, nozzle number and nozzle spray angle on gas-droplet distribution and temperature distribution inside the FGD tower are investigated with numerical simulation based on a Eulerian-Lagrangian mathematical model. An optimal nozzle arrangement scheme is proposed to improve the contact between gas and water droplets and the flue gas temperature distribution. Results show that upward spray direction is beneficial to the interaction between water droplets, improving gas-droplet flow characteristics and spray evaporation process, and water droplets number trapped by tower wall could be reduced in the water droplets evaporation. With the increase in nozzle number, it is conducive to the contact between flue gas and water droplets to increase the evaporation efficiency of water droplets, as well as the uniformity of temperature distribution inside the tower. With nozzle spray angle increases from 30° to 120°, flue gas velocity decreases, water droplets number trapped by the tower wall increases. The temperature distribution at different cross-section is the most uniform when the nozzle spray angle is 60°.

Simulation analysis of gas–solid flow characteristics and water evaporation in flue gas semi‐dry desulphurization process based on CPFD method

AbstractThe gas–solids flow in an industrial‐scale semi‐dry method desulphurization tower is simulated by the computational particle fluid dynamics (CPFD) approach. Compared with previous studies on desulphurization towers, this study focuses on analyzing particle distribution characteristics such as particle volume fraction, temperature distribution, and residence time. The simulation fully considered the particle–fluid, particle–particle, and particle–wall interactions in the desulphurization tower. Based on these considerations, the effects of flue gas inlet velocity and temperature on the gas–solid distribution characteristics of the desulphurization tower are simulated. An optimization scheme for adjusting the gas–solid flow in the desulphurization tower is proposed. The research results show that the error between the CPFD simulation data and experimental data is small and the changing trend is consistent. The particles in the bed of the desulphurization tower show a typical core–annulus flow. The distribution of gas and particles in the bed has a serious deviation with the increase of the flue gas inlet velocity and temperature. As the axial height of the desulphurization tower increases, the flue gas velocity, temperature, particle concentration, and water vapour distribution in the bed become more uniform. The relatively stable operating conditions for the gas–solid flow in the desulphurization tower is that the flue gas inlet velocity and temperature are 15 m/s and 393 K, respectively. Under these operating conditions, the pressure loss caused by the venturi accounted for 73.6% of the total pressure loss of the desulphurization tower. When the particle radius is between 0–150 μm, the particle size and the flue gas inlet velocity have the greatest influence on the particle residence time. Finally, the distribution of gas and particles before and after the adjustment of the desulphurization tower is compared, which showed that adjusting the bottom structure of the desulphurization tower could optimize the gas–solid flow.

Reconstructing 2-D Gas Temperature Distribution With Deep Neural Networks

Acoustic tomography (AT) is considered a promising visualization technique for gas temperature distribution (TD). Generally, a temperature map of a region of interest (ROI) is reconstructed with acoustic velocities of multiple routes inside the ROI using an AT reconstruction algorithm. To improve the accuracy of the reconstruction, increasing the number of iterations is inevitable, which may be time-consuming. Besides, existing reconstruction algorithms rarely consider utilizing practical measurements to improve their performance. In this study, a convolutional neural network (CNN) is proposed to train a machine-learning model that can reconstruct a gas TD from acoustic velocities. By adjusting the label and the loss function, a practical training approach was found. Six models were successfully trained to reconstruct a gas TD. Two were trained with the ideal TD, three were trained with a reconstructed TD, and one was trained with temperatures from specific locations. After that, a TD with peak temperatures located in 13 different positions was applied to test the models’ performance in tracking the hot spot. The results were compared with an existing reconstruction method. Besides, the acoustic velocities from three gas TDs were applied to evaluate the 2-D visualization performance. One of them was similar to the training data and the other two were different. The results indicated that the models trained with the ideal gas TD could track the hot spot more closely, and the models trained with reconstructed gas TDs had similar performance as the selected reconstruction algorithm. However, the 2-D visualization results using models trained with the ideal gas TD were poor compared with models trained with reconstructed TDs when the input acoustic velocities were different from the training data. This indicated that the proposed method could successfully learn the relationship between TD and acoustic velocities from an ordinary reconstruction algorithm. Furthermore, the execution time of the proposed model was 0.109 s, which is 96% less than the selected iterative reconstruction method. Consequently, the proposed neural networks should be considered a reliable and efficient 2-D gas TD reconstruction methodology.

In situ probing of atmospheric-pressure warm air glow discharge for nitrogen fixation by multiple laser spectroscopies

The fixation of atmospheric nitrogen into valuable compounds through reactive plasma processes has attracted intense interests due to its easy operation and compatibility with distributed renewable energy sources. However, practical implementation of plasma-assisted nitrogen fixation is hampered because of its relatively low throughput, which is dominantly limited by the unclear underlying mechanisms. In this study, effort was focused on the in situ production of key species in a DC-driven warm air glow discharge at atmospheric pressure with the help of advanced laser spectroscopic diagnostics. Laser Rayleigh scattering was applied to determine the gas temperature distribution in the discharge column. And mid-infrared quantum cascade laser absorption spectroscopy and one/two-photon absorption laser-induced fluorescence were performed on molecular nitric oxide (NO), atomic oxygen and nitrogen (O, N) for their absolute densities in the discharge. It is found that the spatial distributions of gas temperature, O and N atoms show peaks in the hot discharge center. In contrast, a hollow ‘doughnut’ shape characterized by the NO molecule was observed, particularly under conditions of high discharge current but low airflow rate. The steady-state simulation shows that the hollow pattern of NO is dominantly induced by the radial diffusion of species due to the steep spatial gradient of gas temperature in the discharge cross-section. Moreover, the reverse conversion by atomic N leads to a negative effect on the NO synthesis, especially at the discharge center where the N density and gas temperature are high. From the steady-state modeling, a similar hollow distribution of NO2 was depicted in the air glow discharge. These results demonstrate the strong dependence on atomic O for the major formation process of NO, and the importance of suppressing the reverse paths dominated by atomic N for higher NO production in the studied warm air plasma.

Determination of 915-MHz Atmospheric Pressure Air Microwave Plasma Torch (MPT) Parameters

The gas temperature, electron temperature, and electron density are critical parameters that affect microwave plasma chemistry processes in industrial applications. Using optical emission spectroscopy (OES), the gas temperature and electron density of a 915-MHz atmospheric pressure air microwave plasma torch (MPT) were investigated at various absorbed power levels and radial positions. In addition, the variation in the electron temperatures of 915-MHz atmospheric pressure argon microwave plasma filaments was analyzed as a function of the absorbed power. The experimental results showed that: 1) the absorbed power had little effect on the radial gas temperature or electron density; 2) the skin effect was present in the 915-MHz atmospheric pressure air MPT, where it causing caused hollowing in the center of the radial gas temperature distribution; 3) the electron density reached approximately <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2\times10$ </tex-math></inline-formula> 13 cm−3 and was almost insensitive to variations in the absorbed power in the center of the 915-MHz atmospheric pressure air MPT; and 4) the upper limit of the 915-MHz atmospheric pressure microwave plasma filament electron temperature increased from approximately 1 to approximately 3 eV as the absorbed power increased from 2.0 to 6.3 kW.

Oxidation Enhancement of Gaseous Elemental Mercury Using Waste Steel Slag under Various Experimental Conditions

In this study, the oxidation characteristics of elemental mercury were assessed based on the input gas environment, temperature, and particle size distribution of the steel slag. Experiments were performed at room temperature, 100 °C and 200 °C, under air and simulated gas environments. The oxidation reaction of elemental mercury was conducted using steel slag samples of 1 mm, 2.36 mm, and 4.75 mm at various conditions. From the basic characteristic analysis of the steel slag, it was found that the steel slag exhibits a similar composition to that of fly ash, and it can be utilized as an oxidizing agent. Results show that regardless of the temperature and the particle size distribution of steel slag, the oxidation reaction of elemental mercury rarely occurred in the air environment. However, in the case of the HCl gas environment, it was observed that the smaller the steel slag particle size, the stronger the oxidation reaction. It is believed that the oxidation efficiency of the steel slag increased as the contact area between the gas and particles increased. The oxidation reactivity was nearly two times higher in the temperature range of 100 °C to 200 °C than it was at room temperature. It is advised that further research be undertaken in order to determine the precise temperature range at which the oxidation reaction occurs.

Axial distribution of gas temperature and sound speed in a pipe with a swirled flame

Earlier, an experimental and theoretical study of pulsating combustion in a pipe with a tangential supply of a mixture of propane-butane fuel with air was carried out. It was found that the results of calculating the frequencies of gas oscillations differ significantly from the experimental data. One of the reasons is the hypothetical nature of the axial distribution of the speed of sound in the combustion chamber. In this work, this distribution is found on the basis of calculated and experimental data on the gas temperature at the ends of the pipe.

Gas Temperature Distribution and Fluctuation in a Lab-Scale Fire Whirl

Fire whirls cause an increase in fire damage. This study clarified the unsteady behavior of fire whirls, considering that instantaneous changes in the temperature and flame shape of fire whirls can affect the damage to the surrounding area. Numerical simulations of a lab-scale flame that simulates a fire whirl were performed to investigate the changes in gas temperature and velocity fields under various fuel inflow velocities. The flow field was obtained by solving a continuity equation and a three-dimensional Navier-Stokes equation, and the turbulence was resolved using a large eddy simulation. A chemical equilibrium partially premixed combustion model was used, and radiation effects were considered. The time-averaged gas temperature distribution along the burner central axis revealed that the gas temperature decreased monotonically from upstream to downstream. The time-averaged velocity distribution along the burner central axis showed that the velocity decreased as one moved downstream, but the decrease was uneven. The time variation of the gas temperature demonstrated that the higher the fuel inflow velocity, especially near the burner, the greater the gas temperature flutter. Furthermore, the larger the fuel inflow velocity, the larger the flame swell and wobble. The results showed that the fuel inflow velocity affected temperature fluctuation and flame undulating movement.

Comparative Analysis of Numerical Methods for Simulating N-Heptane Combustion with Steam Additive

Currently, thermal power plants operating on hydrocarbon fuels (gas, fuel oil, peat, shale, etc.) are one of the main sources of electricity. An effective and promising method for suppressing harmful emissions (NOx, carbon oxides, soot) from the combustion of fossil fuels is the injection of steam into the combustion chamber. The influence of various mathematical submodels was studied on the accuracy of the numerical simulation of the process of n-heptane combustion in a laboratory burner with steam additive to the reaction zone as a promising chemical engineering method for the disposal of substandard liquid fuels and combustible waste with the production of thermal energy. The problem was solved in a three-dimensional stationary formulation. Systematic verification of these submodels, and a comparison of the results of the calculation with the experimental data obtained were carried out. The comparison with the experimental data was carried out for gas components and temperature distribution at the burner outlet; high agreement of the results was achieved. Optimal submodels of the methodology for calculating the process of fuel combustion in a jet of steam were determined. The best agreement with the experiment data was obtained using the EDC model in combination with a mechanism consisting of 60 components and 305 elementary reactions. More correct simulation results were obtained using the RSM turbulence model and the DO radiation model.