Effect of fuel injection distance and cavity depth on the mixing and combustion characteristics of a scramjet combustor with a rear-wall-expansion cavity

Ma, Guangwei; Sun, Mingbo; Long, Fan; Yang, Yixin; Huang, Yuhui; Wang, Hongbo

doi:10.1016/j.actaastro.2021.02.020

Cited by 33 publications

(8 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The growing size of the counter-rotating vortex bubbles of the fuel flow increases the contact surface between the fuel and air flows and this has a positive impact on the mixing efficiency. This has also been observed in the studies of Choubey et al [34] and Ma et al [55]. This phenomena can be another reason why the mixing efficiency close to injection ports is higher for observations with a smaller wedge angle (see Fig.…”

Section: Tablesupporting

confidence: 78%

Reduced-order modeling of supersonic fuel–air mixing in a multi-strut injection scramjet engine using machine learning techniques

et al. 2023

View full text Add to dashboard Cite

Section: Tablesupporting

confidence: 78%

Reduced-order modeling of supersonic fuel–air mixing in a multi-strut injection scramjet engine using machine learning techniques

et al. 2023

View full text Add to dashboard Cite

“…The code is designed to solve the internal supersonic combustion problem in the scramjet, which contains complex supersonic turbulent reacting flow. The code has been verified in previous studies [24] for the supersonic mixing process. In this article, the flamelet/progress variable (FPV) combustion model is implanted into the code to simulate the supersonic combustion process, and the following analysis will prove that the code can solve the problem properly.…”

Section: Description Of Numerical Approachmentioning

confidence: 81%

“…To calculate the turbulent viscosity μ t and the Reynold stress τ R ij , the shear stress transport (SST) k − ω model with excellent performance [26] in the supersonic flow is implanted into the code, and the turbulent model has shown good performance in the supersonic mixing flow field in the previous study [24]. For more information about the turbulent model, refer to the study of Li et al [27].…”

Section: ∂ỹ S ∂X Jh S : ð2þmentioning

confidence: 99%

Numerical Investigation of an Axisymmetric Model Scramjet Assisted with Cavity of Different Aft Wall Angles

Sun

Zhao

et al. 2021

International Journal of Aerospace Engineering

Self Cite

View full text Add to dashboard Cite

An axisymmetric model scramjet assisted with cavity flameholder is numerically investigated. Three-dimensional Reynolds-averaged Navier-Stokes simulation is carried out to reveal the fuel mixing and combustion characteristics. The simulation results show reasonable agreements with experimental data. The analysis indicates that the axisymmetric and rectangular scramjet has some similarities to the cavity shear layer in the nonreacting flow field. The configuration of the cavity shear layer changes hugely due to the significant chemical reaction and heat release in the reacting flow field. Typically, two more configurations with different cavity aft wall angles are compared with the experimental configuration to optimize the configuration of the cavity. When the cavity aft wall angle is small, the cavity shear layer bends to the cavity floor and more fuel enters into and stays in the cavity, which results in poor fuel mixing performance. With the increase of the aft wall angle, the fuel distributes more uniformly and the fuel mixing efficiency improves. In the reacting flow field, the volume of the cavity full of hot products and free radicals increases while the interaction between the cavity and main flow decreases with the increase of the aft wall angle. The improved combustion efficiency shows that larger cavity volume weighs more than reduced interaction between the cavity and main flow. The combustion is more violent in the case with a larger aft wall angle. Therefore, a proper increase of the aft wall angle is beneficial to the performance of cavity-assisted axisymmetric scramjet when designing the cavity flameholder.

show abstract

“…The Central Institute of Aviation Engines (CIAM) [15] first introduced the use of cavity structures in the testing of a dual-mode hydrogen-fueled scramjet engine, jointly developed by Russia and France. Subsequently, researchers conducted numerous experimental studies on cavity structures [16][17][18][19][20][21][22]. Micka et al [16] conducted experimental research on a concave cavity dual-mode scramjet engine and identified two different combustion stability modes: concave cavity stable combustion and jet trail stable combustion.…”

Section: Introductionmentioning

confidence: 99%

“…They found that cavities enhance combustion stability, and when the cavity depths are similar, the rear-wall inclined cavity exhibits better fuel mixing and flame stability compared to the rectangular cavity configuration. Ma et al [21] conducted numerical studies using the RANS method to investigate the mixed combustion, with different fuel injection distances and cavity depths. The results showed that shorter injection distances and larger cavity depths reduce shear layer oscillations, leading to strong and stable combustion in the combustion chamber.…”

Section: Introductionmentioning

confidence: 99%

Parametric Study of Flow and Combustion Characteristic in a Cavitied Scramjet with Multi-Position Injection

Xi,

Liu,

Shao

et al. 2024

Fire

View full text Add to dashboard Cite

This study focuses on the three-dimensional flow and combustion characteristics of a cavitied scramjet engine with multi-position injection. A single-equation large eddy simulation (LES) turbulence model is employed, with a detailed reaction mechanism for hydrogen combustion, as described by Jachimowski. The combustion characteristics of hydrogen in the scramjet combustion chamber are analyzed. Based on the combustion chamber model, the influence of different equivalence ratios, injection timing, injection positions, and injection pressures on the flame formation and propagation process are compared. The results indicate that within a certain range, an increase in the equivalence ratio enhances the combustion intensity and chamber pressure. In the case of multi-position injection, the order of injection from different nozzles has little effect on the final flame stabilization mode and pressure distribution. The opposite-side distribution of nozzles can effectively improve the fuel efficiency and the internal pressure. Furthermore, when the nozzles are closely placed in the opposite-side distribution, the combustion efficiency increases, although this leads to a higher total pressure loss. In scenarios where the fuel injection duration is short, an increase in the injection pressure at the upstream nozzles of the cavity results in a higher local equivalence ratio, as well as reduced fuel mixing and ignition time.

show abstract

Effect of fuel injection distance and cavity depth on the mixing and combustion characteristics of a scramjet combustor with a rear-wall-expansion cavity

Cited by 33 publications

References 46 publications

Reduced-order modeling of supersonic fuel–air mixing in a multi-strut injection scramjet engine using machine learning techniques

Reduced-order modeling of supersonic fuel–air mixing in a multi-strut injection scramjet engine using machine learning techniques

Numerical Investigation of an Axisymmetric Model Scramjet Assisted with Cavity of Different Aft Wall Angles

Parametric Study of Flow and Combustion Characteristic in a Cavitied Scramjet with Multi-Position Injection

Contact Info

Product

Resources

About