The recent development of supersonic combustion ramjet engines for augmentation of the mixing performance and improvement in combustion Efficiency: A review

There are several obstacles encountered during combustion in Supersonic Combustion Ramjet (SCRAMJET) engines such as mixing, ignition, and flame holding. In order to overcome these difficulties, a new type of fuel is generated with the use of combination of two methods namely an effervescent (barbotage) and thermal pyrolysis of the fuel. In the first step of the process, during effervescent method, small gas bubbles are introduced into liquid fuel to improve the spraying characteristics of the fuel. At the second stage, long-chain hydrocarbons are broken down into short-chain hydrocarbons that burn faster. An experimental facility has been designed and developed to study the underlying physics in each process.

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Effects of Chemical Reaction Models on Simulations of Scramjet Nozzle Flow

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.490-491.931 ◽

2014 ◽

Vol 490-491 ◽

pp. 931-935

Author(s):

Xiao Yuan Zhang ◽

Li Zi Qin ◽

Yu Liu

Keyword(s):

Kinetic Models ◽

Chemical Kinetic ◽

Numerical Results ◽

Supersonic Combustion ◽

Equilibrium Flow ◽

Reaction Models ◽

Total Temperature ◽

Supersonic Combustion Ramjet ◽

Quantity Of Heat ◽

Non Equilibrium

The chemical non-equilibrium flow of supersonic combustion ramjet (scramjet) nozzle is numerical simulated with different chemical kinetic models to research the effects on numerical results of the nozzle performance. The numerical results show that total temperature is increased due to the recombination of dissociation compositions and the combustion of the residual fuel. The effect of the combustion of the residual fuel is more obvious in this paper, and the effect to the performance of the nozzle is noticeable. The species of the compositions in the models influence the quantity of heat sending out when it get equilibrium, so the 9-species chemical kinetic models are more suitable in the simulation of the scramjet nozzle chemical non-equilibrium flows.

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Numerical Investigation of the Influence of Injection Scheme on the Ethylene Supersonic Combustion

Advances in Mechanical Engineering ◽

10.1155/2014/124204 ◽

2014 ◽

Vol 6 ◽

pp. 124204 ◽

Cited By ~ 4

Author(s):

Hao Ouyang ◽

Weidong Liu ◽

Mingbo Sun

Keyword(s):

Heat Release ◽

Separation Zone ◽

Injection Pressure ◽

Combustion Efficiency ◽

Supersonic Combustion ◽

Recovery Coefficient ◽

Starting Point ◽

Combustion Flow ◽

Inlet Unstart ◽

Pressure Recovery Coefficient

Ethylene supersonic combustion flow field in different injection schemes was studied numerically in the flight Mach 4. The results show that injection pressure has significant influence on the location of the separation zone and the heat release region, but the starting point of the separation region was mostly influenced by the heat release rather than by the injection pressure; the combustion efficiency of the injection schemes including two injection points is higher than that of three injection points, while the total pressure recovery coefficient of the former injection schemes is lower than the latter; excessive ethylene injected in upstream will lead to the change of free-stream flow conditions, which behaves as the inlet unstart in practical application; more ethylene could be injected in downstream to avoid the problem; on the condition of avoiding thermal choke in isolator, it is more advantageous that injection points were arranged more closely to the starting point of separation zone in upside and to the front of the cavity in downside.

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Finite Rate Chemistry Large-Eddy Simulation of Self-Ignition in Supersonic Combustion Ramjet

AIAA Journal ◽

10.2514/1.43746 ◽

2010 ◽

Vol 48 (3) ◽

pp. 540-550 ◽

Cited By ~ 107

Author(s):

M. Berglund ◽

E. Fedina ◽

C. Fureby ◽

J. Tegnér ◽

V. Sabel'nikov

Keyword(s):

Large Eddy Simulation ◽

Supersonic Combustion ◽

Finite Rate ◽

Eddy Simulation ◽

Large Eddy ◽

Supersonic Combustion Ramjet

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Применение вспомогательных топлив для управления сверхзвуковыми потоками реагирующих топливно-воздушных смесей в канале камеры сгорания

Письма в журнал технической физики ◽

10.21883/pjtf.2021.19.51507.18764 ◽

2021 ◽

Vol 47 (19) ◽

pp. 19

Author(s):

С.В. Колосенок ◽

А.Л. Куранов ◽

А.А. Саваровский ◽

П.В. Булат ◽

А.А. Галаджун ◽

...

Keyword(s):

Experimental Model ◽

Laminar Flame ◽

High Reactivity ◽

Supersonic Combustion ◽

Laminar Flame Speed ◽

Combustion Chambers ◽

Gas Dynamic ◽

Dynamic Methods ◽

Combustion Tests ◽

Ramjet Engines

Besides gas-dynamic methods, chemical ones are also suitable for the implementation of stable supersonic combustion of hydrocarbon fuels. Organoelemental compounds are known for their high reactivity, so attention was paid to organosilicon liquid during the research on the experimental model. The obtained estimates of the laminar flame speed in a mixture of vapors of this liquid with air were 0.72-0.8 m/s, which is higher than that of ethylene successfully used in supersonic combustion tests. The tested compound can be considered as a candidate for supplementary fuel to control the supersonic reactive flows in the combustion chambers of ramjet engines.

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Inlet air and fuel flow pressure fluctuation effect on supersonic combustion

Aircraft Engineering and Aerospace Technology ◽

10.1108/aeat-12-2019-0268 ◽

2020 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

AmirMahdi Tahsini

Keyword(s):

Shock Wave ◽

Combustion Chamber ◽

Pressure Fluctuations ◽

Combustion Efficiency ◽

Supersonic Combustion ◽

Oblique Shock Wave ◽

Reacting Flow ◽

Content Type ◽

Fuel Flow ◽

Flow Stream

Purpose The purpose of this paper is to analyze the effect of pressure fluctuations on the combustion efficiency of the hydrogen fuel injected into the supersonic oxidizing cross flow. The pressure fluctuations are imposed on inlet air flow and also on the fuel flow stream. Two different situations are considered: the combustion chamber once without and again with the inlet standing oblique shock wave. Design/methodology/approach The pressure fluctuations are imposed on inlet air flow and also on the fuel flow stream. Two different situations are considered: the combustion chamber once without and again with the inlet standing oblique shock wave. The unsteady turbulent reacting flow solver is developed to simulate the supersonic flow field in the combustion chamber with detail chemical kinetics, to predict the time-variation of the combustion efficiency due to the imposed pressure fluctuations. Findings The results show that the response of the reacting flow field depends on both the frequency of fluctuations and the existence of the inlet shock wave. In addition, the inlet standing shock wave has some attenuating role, but the reacting flow shows an amplifying role on imposed oscillations which is also augmented by imposing anti-phase fluctuations on both inlet and fuel flow streams. Originality/value This study is performed to analyze the instabilities in the supersonic combustion which has not been considered before in this manner.

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