• Proceedings of the KSME Conference
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• 2001.06e
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• pp.494-498
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• 2001

When supersonic jet impinges on wall from the nozzle, complex flow pattern appears such as Mach disc, expansion fan, and jet boundary. The numerical computation of this supersonic jet is important on flame deflecctor design for launch space especially. In this paper, we analyzed supersonic jet structure impinging on deflector wall using three dimensional steady and unsteady compressible equation and showed temperature and pressure distribution on the wall surface. As a result, some dominant factors of jet flows are discussed for conceptual design of flame deflector.

• 한국전산유체공학회:학술대회논문집
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• 2001.10a
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• pp.99-105
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• 2001

Flow computations have been conducted to study the impingement flowfield over the KSR-III flume deflector To validate Euler solver for the jet impingement flowfieid, the jet flow over a double wedge deflector have been calculated and showed reasonable agreement with experimental data. The transient flow behavior of flume over deflector have been investigated and the flume from the rocket nozzle proved to be getting out of the deflector safely and the thermal effect on the base region of rocket was not considerable.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.2
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• pp.98-107
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• 2002

An experimental and numerical study of aerodynamic charateristics of KSR-III and jet impingement on a deflector during launch has been conducted. To investigate aerodynamic characteristics of KSR-III configuration, wind tunnel tests using 6.4% scale model were performed by 4x4 feet ADD trisonic wind tunnel on the Mach number range of 0.4~3.8. Solutions of Three dimensional Euler equations were also obtained and compared with test result. For the study of KSR-III jet impingement flowfield on a deflector during launch operation, unsteady computation using CFD-FASTRAN was performed.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.23 no.2
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• pp.7-14
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• 2015

This paper deals with an optimal determination process for the built-in location of localizer under restrictive siting area conditions of a domestic P-airport. Aerodynamic forces and moments acting on the localizer structure can be used a reference to find the safe distance from jet blast and the position at which the reasonable structural loading is applied. Wind tunnel experiment is conducted to measure aerodynamic loadings. The finite element analysis for structural deformation is employed to get the information of structural failure. A new localizer's position is determined by considering aerodynamic loading, structural strength and thermal loading due to jet blast. Deflector effect was also investigated in this study. In conclusion, the location of localizer can be placed at shorter than the current position and greatly decreased if the deflector is applied at the front of localizer.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.133-138
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• 2012

Exhaust facility has basically the role of flame deflector, and considering additional functions, it can be classified by noise/emission suppressor and altitude simulation facility. In this paper, principles of flame deflector, jet pump, emission suppression are presented for exhaust treatment facility. Principles of noise suppression caused by Mach wave mitigation, jet energy mitigation by water evaporation and condensation are shown. In addition, a concept of vertical exhaust treatment facility is presented applying basic principles aforementioned.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.291-294
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• 2002

This study describes the external spray characteristics of deflector nozzle such as the breakup procedures of liquid sheet, spray angle, discharge coefficient and bubble behaviors of spray and SMD at deflector nozzle. In order to visualize the spray behaviors shadow graphy technique were used. According to the increase of injection pressure, development of the spray passes through the dribbling, distoted jet, closed bubble due to the contraction by surface tension forces, the bubble opens into hollow tulip shape, and the curved surface straightened to form a conical sheet like as the simplex swirl atomizer. Spray cone angle was nearly 90 deg. Variations of SMD were examined in order to describe the dependency of SMD on the injection pressure and orifice diameter. The shape of deflector and oriffice diameter had an effect on the discharge coefficient.

• Journal of ILASS-Korea
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• v.7 no.1
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• pp.29-35
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• 2002

This study describes the external spray characteristics of deflector nozzle such as the breakup procedures of liquid sheet, spray angle, breakup length and bubble behaviors of spray at deflector nozzle. In order to visualize the spray behaviors shadow graphy technique were used. According to the increase injection pressure, deveopment of the spray passes through the dribbling, distoted jet, closed bubble due to the contraction by form a conical sheet like as the simplex swirl atomizer. As trying the analysis of the ratio of bubble length and width it was found that the ratios is comparable. Spray cone angle was nearly $90^{\circ}$.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.7
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• pp.26-31
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• 2003

In this paper, supersonic jets impinging on axisymmetric cone were investigated to obtain fundamental design data for jet deflector case of example being VTOL/STOL or rocket launch. It was of interest to study flow phenomena such as shock interactions and separation induced by shear layer. Experiments were conducted to obtain schlieren flow visualization and measurement of surface pressure. Numerical results are compared with the experimental result. The dominant feature of the flow is the shock pattern induced by the interaction between the cone shock and the barrel shock. This pattern can take a wide variety of forms depending on the structure of the free jet and strongly influences the form of the surface pressure distributions.

• Journal of the Korean Society of Propulsion Engineers
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• v.8 no.1
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• pp.8-15
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• 2004

Supersonic jets impinging on $60^{\cire}$ wedge were investigated to obtain fundamental design data for jet deflector It was of interest to study flow phenomena such as shock interaction and separation induced by shear layer. Experiments using supersonic cold flow system were conducted for Schlieren flow visualization and measurement of surface pressure. Numerical results were compared with the experimental results. The major parameters are underexpansion ratio, distance from nozzle to apex and design Mach number. Flow conditions were obtained for the wedge shock to attach on or detach from the wedge. The dominant feature of flow-field is shock pattern induced by the Interaction between the wedge shock and the barrel shock.

• Journal of the Korean Society of Propulsion Engineers
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• v.5 no.3
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• pp.10-18
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• 2001

In this paper, Supersonic jets impinging on a wedge were investigated in order to acquire fundamental design data for jet deflectors. Surface pressure distributions and pressure contours were obtained using a cold flow tester producing Mach 2 supersonic jets. Schlieren system was used to visualize the flow structure on the wedge surface. Numerical computations were performed and compared with the experimental results. Both results were in good agreement. The results showed that underexpansion ratio did not affect on the surface pressure distribution when the wedge is located at the nozzle exit. With increasing underexpansion ratio, pressure recovery decreased as the wedge is located farther from the nozzle exit. In the pressure contour, it was possible to locate the region where the peak pressure on the wedge surface was occurred.