• 한국연소학회:학술대회논문집
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• 2005.10a
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• pp.261-267
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• 2005

A comprehensive DES quality numerical analysis has been carried out for reacting flows in constant-area and divergent scramjet combustor configuration with and without a cavity. Transverse injection of hydrogen is considered over a broad range of injection pressure. The corresponding equivalence ratio of the overall fuel-air mixture ranges from 0.167 to 0.50. The work features detailed resolution of the flow and flame dynamics in the combustor, which was not typically available in most of the pervious studies. Much of the flow unsteadiness is related not only the cavity, but also to the intrinsic unsteadiness in the flowfield. The interactions between the unsteady flow and flame evolution may cause a large excursion of flow oscillation. The roles of the cavity, injection pressure, and heat release in determining the flow dynamics are examined systematically.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.339-343
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• 2006

Model SCRamjet Engine intake is designed for Ground test. The designed Intake provides hot and slow flow with the combustor. Flow separation is controlled by the shock wave segregation based on the Korekegi criteria. With Kantrowitz limit analysis, side wall cut out region is also set for the self start.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.05a
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• pp.328-331
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• 2008

In order to see the detailed characteristics of model scramjet engine, numerical analysis was performed and compared to the ground test results done by KARI and UQ. Pressure distribution predicted by numerical analysis showed good agreements with test results. Static temperature and pressure distribution explained the mechanisms of cavity flame holder and W-shape cowl which have showed enhancing effects on the supersonic combustion.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.05a
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• pp.307-311
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• 2008

Ground test of model Scramjet engine was performed with T4 free-piston shock tunnel at University of Queensland, Australia. Test condition of free stream was Mach 7.6 at 31 km altitude. With this condition, variation effects of fuel equivalence ratio, cavity, cowl setting were investigated. In the results, supersonic combustion or thermal choking was observed depending on the amount of fuel. Cavity and W-shape cowl showed early ignition and enhanced mixing respectively.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.594-597
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• 2009

The mixing characteristics of pylon injection in a Scramjet combustor and effects of film cooling to protect pylon from air-heating. Three-dimensional Navier-Stokes equations with $k-{\omega}$ SST turbulence model were used. Fuel hydrogen and air were considered as coolants. There were remarkable improvements of penetration and mixing rate with the pylon injection. There also over-heating on the front surface of pylon without film cooling. The coolant injected parallel to the front surface of the pylon protect the pylon from over-heating.

• Journal of the Korean Society of Propulsion Engineers
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• v.9 no.3
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• pp.38-48
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• 2005

For the development of Scramjet engine technology, intake designing processes are investigated. The basic geometry is determined by the inviuld relation such as shock wave relations and geometric relations. Furthermore, bleed duct is installed for preventing boundary layer development and shock wave impingement. Performance of the designed intake is validated by numerical analysis. As a result, double- wedge intake showed better characteristics in total pressure recovery than single-wedge intake.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.267-270
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• 2007

Korea Aerospace Research Institute(KARI) made a scramjet engine test contract with the University of Queensland in October 2006. The experiments were conducted at Mach 7.6, Altitude 31.2 km condition in the T4 free piston-driven shock tunnel in June 2007. In this paper, the short introduction and data processing technique of the T4 free piston-driven shock tunnel will be explained.

• Advances in aircraft and spacecraft science
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• v.2 no.2
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• pp.183-198
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• 2015

Scramjets are a class of hypersonic airbreathing engine that are associated with realizing the technology required for economical, reliable access-to-space and high-speed atmospheric transport. After-burning augments the thrust produced by the scramjet nozzle and creates a more robust nozzle design. This paper presents a numerical study of three parameters and the effect that they have on thrust augmentation. These parameters include the injection pressure, injection angle and streamwise injection position. It is shown that significant levels of thrust augmentation are produced based upon contributions from increased pressure, mass flow and energy in the nozzle. Further understanding of the phenomenon by which thrust augmentation is being produced is provided in the form of a force contribution breakdown, analysis of the nozzle flowfields and finally the analysis of the surface pressure and shear stress distributions acting upon the nozzle wall.

• 한국연소학회:학술대회논문집
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• 2003.12a
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• pp.159-165
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• 2003

This paper describes numerical efforts to characterize the flame-holding and air-fuel mixing process of model SCRamjet engine combustor, where a hydrogen jet injected into a supersonic cross flow and in a cavity. Combustion phenomena in a model SCRamjet engine, which has been experimentally studied at University of Queensland and Australian National University using a free-piston shock tunnel, was observed around separation region of upstream of the normal injector and inside of cavity. The results show that the separation region and cavity generates several recirculation zones, which increase the fuel-air mixing. Self ignition occurs in the separation-freestream and cavity-freestream interface.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.463-466
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• 2010

A scramjet engine intake model was tested with a storage air heater type hypersonic wind tunnel. In test results, there is no large performance change with the variation of the sidewall configurations. In the isolator performance analysis, pressure distribution of oblique shock train and normal shock train was observed. Unstart limit of the model was also confirmed.