Nozzle Velocity Research Articles

Influence of input voltage on the structural and fluid flow characteristics and proposed working condition of a micro-blower

Several methods are explored for the thermal management of highly packed electronic systems. A forced convection setup called micro-blower is an effective solution for the application of heat removal and it consists of a piezoelectric disc (PED), diaphragm, ring and a top plate. A numerical model is developed to study the influence of input voltage on the micro-blower using COMSOL Multiphysics. The size of the micro-blower selected is 20 × 20 × 3 mm3. Structural characteristics such as Eigen frequency, diaphragm displacement and von Mises stress and output characteristic such as velocity at the nozzle exit, the volumetric flow rate of air, density variation in the fluid domain and pressure gradient of air at the nozzle for various voltage inputs (peak-to-peak voltage, Vp-p) from 5 to 20 V were estimated. The diaphragm displacement of the blower was estimated with various input voltages. An average nozzle velocity of 21.21 m/s was achieved with an average volumetric flow rate of 10.66 × 10−6 m3/s for the voltage input of 20 Vp-p. The von Mises stresses of PED, diaphragm, ring and top plate were 3.38, 6.38, 15.72 and 88.97 MPa and these were within the maximum yield strength of respective components at 20 V and hence the micro-blower design is safe. The proposed Eigen frequency in the ultrasonic range was 21.298 kHz and the proposed input voltage as per the breakdown voltage was 20 V. The results were compared with existing literature data and found promising agreement.

Laser Velocimetry for the In Situ Sensing of Deep-Sea Hydrothermal Flow Velocity.

Laser Doppler velocimetry (LDV) based on a differential laser Doppler system has been widely used in fluid mechanics to measure particle velocity. However, the two outgoing lights must intersect strictly at the measurement position. In cross-interface applications, due to interface effects, two beams of light become easily disjointed. To address the issue, we present a laser velocimeter in a coaxial arrangement consisting of the following components: a single-frequency laser (wavelength λ = 532 nm) and a Twyman-Green interferometer. In contrast to previous LDV systems, a laser velocimeter based on the Twyman-Green interferometer has the advantage of realizing cross-interface measurement. At the same time, the sensitive direction of the instrument can be changed according to the direction of the measured speed. We have developed a 4000 m level laser hydrothermal flow velocity measurement prototype suitable for deep-sea in situ measurement. The system underwent a withstand voltage test at the Qingdao Deep Sea Base, and the signal obtained was normal under a high pressure of 40 MPa. The velocity contrast measurement was carried out at the China Institute of Water Resources and Hydropower Research. The maximum relative error of the measurement was 8.82% when compared with the acoustic Doppler velocimeter at the low-speed range of 0.1-1 m/s. The maximum relative error of the measurement was 1.98% when compared with the nozzle standard velocity system at the high-speed range of 1-7 m/s. Finally, the prototype system was successfully evaluated in the shallow sea in Lingshui, Hainan, with it demonstrating great potential for the in situ measurement of fluid velocity at marine hydrothermal vents.

Numerical investigation on spray and flow field characteristics of elliptical nozzle in supersonic crossflow

ABSTRACT It has been suggested that using an elliptical nozzle could enhance the atomization and mixture quality. In order to explore the elliptical liquid jet on spray and flow field characteristics in supersonic airflow, the VOF-Spray one-way coupling model was adopted to study the nozzle exit patterns, size, and velocity distribution of droplets. The research also compared the flow field characteristics in Mach 2.85 air crossflow under the application of different orifices. The numerical results showed that elliptical 4 nozzle (Aspect ratio of 4) had better flow performance than circular nozzle. The cavitation area and turbulent disturbance of elliptical 4 nozzle were mainly concentrated in the major axis direction. The elliptical 4 jet always had a lower penetration depth than circular jet. At the flow range of 0 ~ 50 mm, the penetration depth of elliptical 4 jet is roughly 12% less than that of circular jet. Another finding was that the spanwise extension range of elliptical 4 spray was larger than the circular spray. The spanwise extension range of elliptical 4 spray increased by about 19.4% at most in the flow range of 0 ~ 50 mm. Additionally, the elliptical 4 spray had the smallest Santer Mean Diameter (SMD). The elliptical 4 jet had a 2.9% smaller Santer Mean Diameter than the circular jet. Due to the greater windward surface area of the elliptical 4 orifice, the gas streamwise velocity near the bottom wall was reduced. A reverse vortex pair with distinct characteristics could be observed under the application of elliptical 4 orifice. Furthermore, compared with the circular orifice, the shock wave angle generated by elliptical 4 orifice reduced by 9.7%, and the total pressure recovery coefficient rose by 2.3%.

The Effect of Hydrogen on Nonlinear Flame Saturation

Abstract We investigate the effect of increasing levels of hydrogen enrichment on the nonlinear response and saturation of premixed bluff-body stabilized methane/hydrogen flames submitted to acoustic forcing. The thermal power is kept approximately constant to preserve the nozzle velocity while increasing the flame speed through hydrogen enrichment. The flame describing function (FDF) is measured for a fixed frequency and three hydrogen–methane blends ranging from 10% to 50% by power, corresponding to 25% to 75% by volume. We show that when the flame is forced at the same frequency at similar power and bulk velocities, increasing levels of hydrogen enrichment increase the saturation amplitude of the flame. To provide insight into the flame dynamics responsible for the change in the global nonlinear response and saturation amplitude, the flames were investigated using high-speed imaging in combination with OH planar laser-induced fluorescence (OH-PLIF) at a range of forcing amplitudes. At lower hydrogen concentrations, the flame is stabilized along the inner shear layer and saturation in the heat release rate (HRR) occurs at lower forcing amplitudes due to large-scale flame–vortex interactions causing flame annihilation as observed in several previous studies. At increased levels of hydrogen enrichment, distinctly different flame dynamics are observed. In these cases, the flame accelerates and propagates across to the outer shear layer, which acts to suppress large-scale flame annihilation during roll-up of both the inner and outer shear layers. This results in a coherent increase in flame surface area with forcing amplitudes significantly increasing the saturation amplitude of the flame. These results show that high levels of hydrogen increase the amplitude response to acoustic forcing leading to higher saturation amplitudes. This suggests that substituting natural gas with hydrogen in gas turbines increases the risk of much higher limit-cycle amplitudes if self-excited instabilities occur.

Modeling fiber orientation and strand shape morphology in three-dimensional material extrusion additive manufacturing

The fiber orientation in composite materials is highly dependent on the manufacturing process and plays a crucial role in determining the mechanical, thermal, and electrical properties of the fabricated parts. Several simulation frameworks have been developed to predict the fiber orientation in the printed strands for Material EXtrusion Additive Manufacturing (MEX-AM) process, but studies have been limited to planar and 2D model reductions. Consequently, it is currently impossible to predict the full spatial variation of fiber orientations in a three-dimensional printed strand, and thus the effects of printing conditions remain not well understood. This work seeks to address this issue by introducing the first three-dimensional model capable of simulating the MEX-AM process with fiber-reinforcements. A fully coupled model is developed in this work, which is based on the finite-volume method and solved in the open-source multiphase software OpenFOAM. Using this framework, we explored the effects of different printing conditions on fiber orientation and strand shape morphology, and we compared our results to experimental observations when possible. We found that the extrusion and nozzle velocities significantly affected the fiber orientation while altering the gap distance between the nozzle exit and substrate had a limited impact. Moreover, increasing anisotropy using longer fibers and higher volume fractions had little influence on the fiber orientation, but their impact on the rheology altered the strand shape considerably. Prediction of fiber orientation for different printing conditions within strands will open the possibility of manufacturing products that has locally engineered properties and tailored anisotropic behavior.

Rheology-informed hierarchical machine learning model for the prediction of printing resolution in extrusion-based bioprinting

In this study, a rheology-informed hierarchical machine learning (RIHML) model was developed to improve the prediction accuracy of the printing resolution of constructs fabricated by extrusion-based bioprinting. Specifically, the RIHML model, as well as conventional models such as the concentration-dependent model and printing parameter-dependent model, was trained and tested using a small dataset of bioink properties and printing parameters. Interestingly, the results showed that the RIHML model exhibited the lowest error percentage in predicting the printing resolution for different printing parameters such as nozzle velocities and pressures, as well as for different concentrations of the bioink constituents. Besides, the RIHML model could predict the printing resolution with reasonably low errors even when using a new material added to the alginate-based bioink, which is a challenging task for conventional models. Overall, the results indicate that the RIHML model can be a useful tool to predict the printing resolution of extrusion-based bioprinting, and it is versatile and expandable compared to conventional models since the RIHML model can easily generalize and embrace new data.

“The effect of the nozzle blade pitch on the velocity coefficient of the inflow turbine with partial blading of the runner

A numerical experiment with three groups of low-consumption inflow turbine with partial blading of the runner is considered in the paper. Geometric models of turbine stages with partial flapping of the runner with different grid spacing of the nozzle diaphragm have been developed. The object of this study is centripetal turbine stages with partial flapping of the impeller. The subject of the study is the efficiency coefficient and the velocity coefficient of the nozzles of the inflow turbine. The research method is numerical simulation of the working fluid flow using elements of computational gas dynamics. The aim of the study is to determine the effect of the nozzle blade pitch on the efficiency of the nozzle diaphragm of low-consumption inflow turbine with partial blading of the runner. The main objectives of the study are creating geometric models of turbine stages with different nozzle pitch, determining the boundary conditions of the experiment, conducting and processing the results of the experiment. The graphs of the dependence of the nozzle velocity coefficient and the efficiency of the low-consumption inflow turbine stage are provided. A comparative analysis of the nozzle velocity coefficient and the efficiency coefficient of three turbine stages with different grid spacing of the nozzle diaphragm is carried out. The velocity fields of the flow part of the turbine stages and the integral values of the parameters necessary for the three-dimensional calculation are obtained. The influence of the nozzle blade pitch on the velocity coefficient of the nozzle diaphragm and the efficiency coefficient of the turbine stage is determined. The nature and dependence of this geometric parameter on the efficiency of the study object is established, conclusions on further improvement of turbine stages with partial blading of the runner are made.

Maximal utilization of purge gas in methanol plants with improved primary furnace burners: A CFD study

The focus of this study is to achieve a better design of burners installed in petrochemical steam methane reformeing (SMR) furnaces. The initial design for the burners of the primary furnace in the Marjan petrochemical plant was problematic; hot spots occured on the side walls of the radiant chamber when the purge gas of the plant was added to the fuel stream. Three distinctive improvements have been recommended to alleviate this problem and provide higher combustion efficiency. These three suggestions include introducing pre-mixing of air and fuel streams, lowering the fuel nozzle velocity, and additional staggered nozzle holes to the base design to achieve more uniform flames. The non-premixed combustion computational fluid dynamics (CFD) simulations are conducted with ANSYS Fluent software on only one array of the burners, given the periodic boundary conditions at the two sides of each array. The resulting temperature and velocity distributions are obtained to compare the designs. The results indicate that a more uniform temperature distribution will be achievable by adding the staggered nozzle holes, which provide a heat flux of 7604 W/m2 and reduce the radiant wall’s average temperature by 0.598%. However, the combustion phenomenon occurs at its highest efficiency—99.998%—through the second design, where the fuel velocity is lowered at the nozzles. Although the first design with the pre-mixing of air and fuel performs more effectively in pushing flame towards the reformer tubes and reducing temperature variations along the radiant walls, the possibility of flash-back occurrence is high; so further safety actions must be taken into account. Eventually, the third design is chosen for implementation as economic analysis indicates that $10 million/year will be saved by lowering the amount of natural gas injected into the burners.

Influence of Impinging Jet Nozzle Movement on Heat Transfer Characteristics of a Flat Plate

Abstract The purpose of the current experimental study is to assess the influence of impinging air jet movement on the heat transfer of a fixed flat plate. The experiments are conducted with varying the nozzle velocity (Vn) from 400 to 1000 mm/min, and the Reynolds number (Re) from 8000 to 20,000 at a nozzle-to-plate distance (H/D) of 2 and 6. A comparison between a movable nozzle and a fixed nozzle based on the temperature contours and local Nusselt number is presented. Additionally, the local Nusselt number, heat transfer uniformity index, and uniformity of heat transfer are evaluated. The results demonstrate that the local Nusselt number of 24.8 has a maximum value at a Vn of 400 mm/min, a Re of 20,000, and a H/D of 2. The uniformity of heat transfer is enhanced by increasing the Vn, and its maximum value of 89.5% is maintained at a Vn of 1000 mm/min, Re of 20,000, and H/D of 6. Additionally, the heat transfer uniformity index decreases with increasing the Vn where its maximum value is 0.34 at a Vn of 400 mm/min, a Re of 8000, and a H/D of 2.

Dynamics model and numerical simulation of single stage water rocket

The initial launch parameters of a water rocket have a significant impact on its speed, altitude and other flight performance. The dynamic model describing the mass, velocity, nozzle velocity and internal pressure of water rocket was established by the force analysis of its ascending stage. Numerical simulation was carried out on the movement process of the water rocket. The changes of the internal pressure and thrust of the rocket body, and the speed and height law of the rocket in the flight process under the conditions of the same initial internal pressure and different initial loading propellant liquid were studied respectively. The results show that, under the designed conditions, the change law of the thrust force is similar to the variation of the internal air pressure in the ascending stage, and the internal air pressure decreases to 45%~57% of the initial value at last. Setting the volume of the initial loaded liquid to 0.43 helps to increase the boost duration and improve the utilization of the initial pressure, in which case, the maximum velocity of the launch rocket is not affected, but will lead to a decrease in thrust size.The above results provide important technical support for the optimal design of single-stage or multistage water rocket, and have strong guiding significance for carrying out water rocket flight test.

Влияния угла наклона сопел на коэффициент скорости центростремительной турбины с частичным облопачиванием рабочего колеса

The paper considers a numerical experiment with three groups of low-consuming inflow turbines with partial blading of the runner. Geometrical models of the turbine stages with partial blading of the runner at different angles of the nozzle inclination have been developed. The inflow turbine stages with partial blading of the runner are investigated. The efficiency and speed coefficient of the inflow turbine nozzles are calculated. There has been carried out numerical modeling of the working fluid flow by using the computational gas dynamics elements. Pick values of the nozzle apparatus velocity coefficient and the turbine stage efficiency are defined. Geometric models of the turbine stages with different nozzle inclination angles are developed, the boundary conditions of the experiment are determined, and the experiment results are analyzed and shown. There are given the dependence graphs of the nozzle velocity coefficient and the efficiency of a low-consuming inflow turbine stage. Comparative analysis of the nozzle velocity coefficient and the efficiency of three turbine stages with different inclination angles of the nozzles in the nozzle apparatus has been carried out. Conclusions are drawn about further procedures on improving the flow part of the runner to increase the efficiency of the stage.

Scalings and decay of homogeneous, nearly isotropic turbulence behind a jet array

In the study of dispersed multiphase turbulence, using a jet array has shown promise in creating intense homogeneous, nearly isotropic turbulence with high dissipation rates in water and wind tunnels. However, the scaling of turbulent characteristics with jet nozzle diameter, velocity, and downstream location has not been fully explored. Our research, combined with previous experiments focusing on near-field measurements, offers a comprehensive understanding of the decay of kinetic energy and energy dissipation rate, as well as the flow inhomogeneity and anisotropy generated by a jet array.

Effect of spray operation conditions on Nox emission control in a power station

Adequately mixing of reactants is an important factor for efficient deNOx process in power station NOx emission control system. In this study, an experimental validated CFD simulation is conducted to investigate the effect of spray operation conditions on the mixing uniformity of reactant ammonia vapor in deNOx process occurring in a power station’s furnace. According to the CFD simulation results, it is found that spray momentum ratio, initial droplet size and initial ammonia concentration all affect the mixing uniformity of ammonia vapor. Overall, a larger spray momentum ratio, larger initial droplet size and lower ammonia concentration contributes positively to the mixing uniformity. By comparing the same spray momentum ratio but different nozzle inlet velocity and furnace inlet velocity, it is found that the impact of spray momentum ratio mainly comes from furnace inlet velocity not nozzle inlet velocity. In addition, gravity should not be neglected. In the end, the method described in this study could provide a systematic way to study the effects of nozzle operation conditions on deNOx process.

Influence of Nozzle Layouts on the Heat-Flow Coupled Characteristics for Oil-Jet Lubricated Spur Gears

Aiming to explore the influence of nozzle layouts on the lubrication and cooling performance of spur gears under oil jet lubrication conditions, this paper introduces a heat-flow coupled analysis method to predict the temperature field of the tooth surface with different nozzle layouts. Firstly, the friction heat formulas integrating the coefficient of friction and average contact stress are presented for calculating heat generation. We also present the impingement depth model, which considers the nozzle orientation parameters, jet velocity, and gear structure of the given spur gear pair for laying out the nozzle. Then, a heat-flow coupled finite element analysis method is exploited to resemble the jet lubrication process and gain the gear temperature characteristics. Finally, the numerical results of this model compare well with those of the experiments, showing that this heat-flow coupled model provides accurate temperature prediction, indicating that the nozzle layouts determined as a function of the oil jet height, deviation distance, and oil injection angle significantly influence the lubrication and cooling performance. Further, this study also reveals that the lubrication performance in cases where the nozzle approaches the side of the pinion is relatively superior.

Scenarios of combustion of plane hydrogen microjets at sub- and supersonic velocities

Experimental data on diffusion combustion of plane hydrogen microjets emanating from a slotted micronozzle at subsonic and supersonic velocities are reported. Four scenarios of diffusion combustion of the hydrogen microjets are presented. As is found, the stabilization of subsonic combustion of the hydrogen microjet is related to the origination of a “bottle-neck” configuration of flame while in supersonic conditions the flow pattern is dominated by supersonic cells. Hysteresis of the diffusion combustion of plane hydrogen microjet is found depending on its ignition far from or close to the nozzle exit and velocity variation.

Preliminary design and simulation of an innovative Rotary Supersonic Nozzles Expander apparatus for natural gas liquefaction and general refrigeration processes

An innovative method and a supersonic expansion apparatus proposed for the natural gas liquefaction process and the potential to use in general Refrigeration purposes, gases separation, CO2 capture and air conditioning. The current study presented the innovated apparatus features preliminarily, described its design basics and working principles, and outlined general schemes of approached method implementations. The apparatus named the Rotary Supersonic Nozzles expander. The apparatus designed on the basis of the compressible flow and the fundamentals of the Laval nozzle and the supersonic separation process. It is an Expansion bladeless turbomachinery utilizes the propulsion reaction principles of the Rocketry Engines. The numerical analysis and CFD simulations were conducted to investigate the influences of the nozzle backward reaction velocity on the supersonic flow distributions and to determine the enhancements achieved in the gas cooling and condensation processes by the proposed apparatus compared with the existing supersonic separators. CFD executed based on the anticipated nucleation theories and condensation models. Simulation results confirmed that fluid stagnation properties in the proposed apparatus exposed unacquainted behaviors during the rotational motion and their distributions diminished along the nozzles. The proposed apparatus obtained an extraordinary improvement in the supersonic expansion and condensation process. The estimated maximum nucleation rate 1.80707e + 037 m−3 s−1, which was about 10e + 14 times the existing rate in the statical nozzle at the same conditions. Similarly, the estimated maximum droplets number and mass transfer rate were about 10e + 08 and 14 times respectively. The obtained maximum liquid mass fraction was 0.6 and 5.75 times more than that achieved by the static nozzle. Furthermore, the estimated shaft power recovery was>50 % of the required power to obtain the same compression ratio.

Effect of the length of truncated nozzle with a tip on its thrust characteristics

Nowadays, for solving new problems, rocket engine nozzle developers are increasingly turning to non- traditional nozzle configurations that differ from the classic Laval one. A relatively new line in the design of supersonic nozzles is the development of the so-called bell-shaped nozzle, which, unlike the classical Laval nozzle, has a larger angle of entry into the supersonic part of the nozzle. In this case, dual bell nozzles, which have two flow expansion sections in their supersonic part, are considered. However, the effect of the length ratio of the two flow expansion sections of a truncated nozzle on its characteristics has not yet been studied. The goal of this work is to determine the effect of the length of the upstream conical supersonic section on the static pressure distribution in the nozzle and its thrust characteristics with the shape of the bell-shaped tip kept unchanged. The nozzle characteristics were studied using the ANSYS Fluent computing package. It was shown that the flow patterns in the nozzle (velocity fields) change with the length of the conical part upstream of the tip and the underexpansion degree. Under terrestrial conditions (Pн = 1 bar), all variants show a developed separation zone that starts from the corner point where the tip is connected to the conical part. In this case, the pressure on the nozzle wall is nearly equal to the ambient pressure. At a large flow underexpansion degree (P0 = 300 bar) and in low-pressure conditions conditions (Pн =0.1 bar), the flow in the tip is adjacent to the wall. At a large flow underexpansion degree, the pressure in the nozzle increases from the corner point to the tip exit, and the pressure at the tip exit increases with decreasing tip length. The nozzle thrust coefficient decreases with increasing flow underexpansion degree, and it reaches a constant value after the flow becomes adjacent to the tip wall downstream of the corner point where the tip is connected to the nozzle. At high flow underexpansion degrees, the nozzle thrust coefficient is higher for a nozzle with a longer conical part. The calculated results are in good agreement with experimental data on nozzles of this type.

Self-charging of sprays

The charging of poorly conducting liquids due to flows is a well-known phenomenon, yet the precise charging mechanism is not fully understood. This is especially relevant for sprays, where the spray plume dynamics and maximum distance travelled of a spray dramatically changes for different levels of charging: charging of the droplets makes them repel, thereby preventing drop coalescence and altering the shape of the spray plume. As the charging depends on many factors including the flow and the interactions between the liquid and the nozzle, many models and scaling laws exist in the literature. In this work we focus on perhaps the simplest flow regime, laminar jets created by ultra short channels, and quantify the charging as a function of the different parameters. We present a simple model that collapses all the data for over 4 orders of magnitude difference in streaming currents for various nozzle sizes, flow velocities and surface treatments. We further show that the charging polarity can even be reversed by applying an oppositely charged coating to the nozzle, an important step for any application.

The low frequency pressure pulsation and control of the open-jet wind tunnel

An open jet wind tunnel has low-frequency pressure pulsation in common wind speed range due to its unique structural form, which seriously damages the quality of flow field in the test section. The low-frequency pressure fluctuation performance and control mechanism of Jilin University open jet and return flow wind tunnel are investigated by experiments and numerical simulation. The results show that the low-frequency pressure fluctuation is a narrow pulse phenomenon that only occurs in certain intervals, and several velocity intervals may be found in the same wind tunnel. The reliability of the numerical simulation is verified by comparing the peak frequency and amplitude of pressure fluctuation in numerical simulation and wind tunnel tests. A simplified model similar to and amplifying the phenomenon is established. The flow structure and vortex evolution are analyzed via detached eddy simulation. In the test section, large-scale shedding vortices are formed at the nozzle exit, introducing periodic pulsating instantaneous velocity and acting with the collector to form an edge-feedback. This acoustic feedback forms resonance with the pipeline circuit, resulting in poor flow field quality. In accordance with the mechanism of nozzle jet, two methods of controlling pulsation are proposed: spoiler and flow-follow device. The study shows that the effects of two methods are abrupt, and the frequency of pressure pulsation is changed. The spoiler destroys the complete structure of vortex ring in free jet and develops into a complementary double vortex ring structure, which is highly sensitive to size factors. The flow-follow device supplements the velocity loss of the free jet at the nozzle and develops into a double vortex ring with master–slave structure in the middle of the test section. Its vibration reduction effect is greatly affected by the flow velocity. It takes effect in an appropriate range where the flow velocity is higher than the nozzle velocity. If the follow velocity is extremely low, the flow-follow device cannot change the original jet structure. If the follow velocity is extremely high, the momentum of the fan will be greatly reduced, the flow field will be unstable, and another order of pulsation may be induced. This work lays a solid foundation for further understanding the aerodynamic characteristics and optimization mechanism of open jet wind tunnel.

Influence of nozzle structure on the combustion performance of a graphitic hydrogen-chlorine synthesis combustor

The growing semiconductor sector is driving up demand for high-purity gas-phase HCl. Large combustion zones and low HCl concentrations are problems for HCl manufacturing systems. Based on the realizable k-ε model, the eddy breakup combustion model, and the participating media radiation model, the computational fluid dynamics simulation was used as the primary means in this study. The influence of four structural factors, nozzle jet hole diameter, jet angle, and opening angle—another is nozzle mounting height, on the combustion effect of the synthesis combustor was investigated. The extent of the high-temperature zone in the synthesis combustor and the purity of the hydrogen chlorine at the outlet were used as the main evaluation criteria. The results of numerical simulations demonstrate that the better the gas mixing and combustion in the combustor, the lower the nozzle mounting height should be. Small nozzle diameters and large nozzle jet angle increase gas flow velocity in the recirculation zone close to the inner wall of the combustor. Additionally, the recirculation zone will appear in the combustor as a result of the nozzle's presence. The area of the high-temperature zone within the combustor decreases as internal gas velocity increases. On the other hand, the recirculation gas flow is not significantly impacted by the angle at the condition that the jet holes open. The results of the investigation provide a reference for the design of the miniaturization of the combustor in the non-premixed combustion synthesis of gases process.