Ramjet engine testing and simulation techniques

Supersonic single-mode ramjet performance was analyzed using a prescribed two-dimensional conical shock wave in axisymmetric supersonic flow. The ramjet under consideration for the analysis consists of a mixed compression intake, a cylindrical combustion chamber and a supersonic constant convergent-divergent nozzle. A computer program was developed to carry out the analysis based on the formation of multiple conical shock waves at the engine intake at different flight Mach numbers and different altitudes in the range of 1.5-4 Mach and 9000-18,000 m, respectively. Accordingly, a supersonic convergent-divergent nozzle was designed and consequently, the area ratios along the ramjet were calculated to find the correct dimensions for the thrust required. The analysis of the multi-shock system showed that for a given number of conical shocks and Mach numbers, the thrust decreases as the altitude increases. Also, the thrust increases at higher Mach numbers and higher number of conical shocks regardless of the altitude. Furthermore, for M42:5, and at number of conical shocks greater than 2, thrust stays constant. The flow rate and the pressure after combustion showed similar trends as the thrust. The multi-shock system of the intake system proposed showed that a limit of a three conical shocks were sufficient for a reasonable pressure recovery for a M42, while for a M52, a single normal shock wave could be sufficient for different altitudes. Also, pressure recovery is unaffected by the altitude for the same Mach number and increases with lower Mach numbers. Moreover, the increase of number of conical shocks is limited to 3 where no further increase in pressure recovery could be indicated.

show abstract

“…By using equations (11), (13), (14) and the expression tan 2 s ¼ cos À2 s À 1, we obtain the boundary condition on the shock…”

Section: Choice Of Intake (Conical Shocks)mentioning

confidence: 99%

The effect of multiple conical shock waves at the engine intake on the performance of a single-mode ramjet

Ebaid

Al-khishali

2013

Proceedings of the Institution of Mechanical Engineers, Part G:

View full text Add to dashboard Cite

show abstract

“…Connected-pipe tests have been conducted in numerous studies on ramjet and scramjet systems [13,18,19] to demonstrate the combustor performance using accurate §ow conditions and to investigate the combustion phenomena of air-augmented combustors. Figure 1 shows a schematic of the connected-pipe test facility for the lab-scale ducted rocket, which was designed at the Fine Rocket Propulsion Center of the Technion ¡ Israel Institute of Technology.…”

Section: Experimental Setup For a Connected-pipe Testmentioning

confidence: 99%

Experimental investigation of the effect of the air inlet angle and the combustion pressure in a ducted rocket combustor

Laguzzi

Molinaro

Natan

2019

Progress in Propulsion Physics – Volume 11

View full text Add to dashboard Cite

The scope of the study is to evaluate the combustion efficiency of a ducted rocket combustor operating at different conditions, using a connected-pipe testing setup. An experimental parametric investigation was conducted to evaluate the effect of the inlet air-injection angles and the effect of the combustion pressure for different fuel-to-air ratios. The experimental results indicate that best energetic performance was obtained for an injection angle of 120°, i. e., against the main flow direction. The reason is that this way better mixing was obtained and the residence time increased. Characteristic velocity was found to decrease with decreasing the combustion pressure.

show abstract

“…Due to its low cost and simplicity, the direct-connect testing technique has been used as a mature experimental method for air-breathing ramjet engines for decades [13,14]. A vitiated heater is commonly used to simulate stagnation temperatures and pressures of the incoming air in real flight con ditions, whereas for the underwater application of the ramjet engine, owing to the incompressibility of water flow, only mass flow rates and elevated pressures need to be duplicated at the water inlets, for which the design considerations are simplified for testing system.…”

Section: Testing Systemmentioning

confidence: 99%

Performance study of a water ramjet engine

Huang

Xia

et al. 2011

Sci. China Technol. Sci.

View full text Add to dashboard Cite

A performance study of a water ramjet engine is described. The engine is powered by the reaction of a magnesium-based propellant and ingested water. In this study, a solid propellant, which consisted of a large percentage of magnesium, a binder and a small amount of oxidant, was used as a hydro reactive fuel. Cold water was injected into the combustion chamber as a main oxidant. A scaled-down experimental engine was tested in a direct-connect ground testing system to characterize the factors influencing the engine performance. The results show that the increasing of total water/fuel ratio, an addition of secondary water intake along the combustion chamber, a larger magnesium content in the solid propellant, a smaller primary water injection angle towards the coming main flow, and a higher primary injection pressure were all able to promote the engine performance. The maximum engine performance was obtained in test 08, and with all tests, an appropriate set of parameters and conditions for the optimum engine performance were determined underwater propulsion system, ramjet engine, magnesium, water, combustion, performance, experiment Citation:Huang L Y, Xia Z X, Hu J X, et al. Performance study of a water ramjet engine.

show abstract

Ramjet engine testing and simulation techniques

Cited by 5 publications

References 0 publications

The effect of multiple conical shock waves at the engine intake on the performance of a single-mode ramjet

The effect of multiple conical shock waves at the engine intake on the performance of a single-mode ramjet

Experimental investigation of the effect of the air inlet angle and the combustion pressure in a ducted rocket combustor

Performance study of a water ramjet engine

Contact Info

Product

Resources

About