• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.05a
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• pp.171-176
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• 2006

An experimental study on a fuel-rich gas generator was carried out. Thirty seven double-swirl injectors with recess number of 1.5 were distributed and installed in the injector head, which significantly influences the combustion performance. In the paper, the characteristics of combustion stability are inspected by the parametric varations such as changing length and diameter of a combustion chamber and installing a turbulence ring. The experimental results show that as a resonant frequency took place in a high region, the amplitude of the dynamic pressure generally diminished, however, the combustion instability could not be suppressed perfectly.

• Journal of the Korean Society of Propulsion Engineers
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• v.10 no.4
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• pp.85-92
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• 2006

A design program has been developed to predict film cooling performance of a liquid rocket engine. A thermal protecting effect of low mixture ratio gas layer has been analysed by CFD. A one-dimensional film cooling model based on the CFD results has been implemented to the previously developed design program of regenerative cooling. Satisfactory agreement has been achieved by comparing the predicted maximum heat flux at the throat of a subscale chamber and the average measured value, and the predicted nozzle average heat flux and the measured value for a full scale chamber with film cooling. It is ascertained that the film cooling is effective to reduce the throat heat flux in rocket engine chamber.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.553-556
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• 2009

In this study, ignition tests of a gas turbine combustor were performed to evaluate an ignition loop at low temperature condition. An experimental setup was constructed to simulate low temperature condition with a heat exchanger using dry ice as a coolant. Various low temperature conditions could be created by controlling the amount of air though the heat exchanger. The results showed that ignition limit decreased with air temperature.

• Journal of The Korean Digital Architecture Interior Association
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• v.13 no.4
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• pp.25-32
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• 2013

The green building is one of biggest factors to go the goal of energy saving and environmental conservation, reduction of energy consumption, friendly energy technology, recycling of resource, and environmental pollution reduction technology. The purpose of these green buildings realized by the energy-saving technology such as the exterior materials or curtain wall system. The curtain wall system is a element that come to insulated portions of building envelope that results in heat loss. The purpose of this paper is to carried out mock-up tests for exterior wall used in autoclaved lightweight concrete panels in green building practices. Mock-up test execute a mixed process between standard test procedure and complex test procedure based on AAMA 501(American Society for Testing and Materials) and ASTM 283, ASTM 330(American Society for Testing and Materials). In results, tests meet the requirements that grant values in steps of procedures provided on ASTM and AAMA. ALC panel is suitable for a exterior wall product to be gratified thermal cycling performance and structural capacity, deflection(H/200) and lateral displacement(H/50), for curtain walls.

• Geotechnical Engineering
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• v.14 no.5
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• pp.17-28
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• 1998

The design of a ground anchor wall calculating the design anchor force and anchored walls depends primarily on the earth pressure acting on anchored w deflection of the wall, the wall stiffness, distribution exists for anchored walls. In the apparent earth pressure envelope design of anchored walls. In this study, full scale anchored w pressure distribution was obtained from function. Earth pressures obtained from pressure and with the apparent earth pre the anchored wall in sand. It is conclude is appropriate for the anchored wall design.

• Fire Science and Engineering
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• v.25 no.4
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• pp.94-102
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• 2011

Hot smoke test is done in a subway tunnel. Alcohol trays of 1.0 MW and smoke generators are used for generating hot smoke. The fans equipped with the tunnel are successively run 9 min after smoke generation. It is verified how hot smoke is controlled by fans. Velocity and direction of flow, temperature and smoke density are measured and analyzed for smoke control performance of the tunnel with fans and analyzed from the fire-safety-point of view. Velocity of smoke flow is obtained by using measured velocity and temperature at the ceiling of the tunnel. The time when smoke-control flow is builded up is different for the different positions. Velocity distributions at various positions will be used for the boundaries and the comparison data in numerical simulations for evaluation on smoke-control facilities of subway tunnel.

• Journal of Korean Society of Steel Construction
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• v.14 no.5 s.60
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• pp.593-602
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• 2002

A new type of bridge superstructures referred to as Steel-Confined Prestressed Concrete Girder (SCP Girder) was developed, which is composed of concrete, steel plate, and prestressing tendon. The girder may maximize structural advantages of these components; thus, long span bridges with low height girder may be constructed. For the effective design and fabrication of the gilder, the design software program was developed and the process of fabrication established. The experimental girder designed using the program was manufactured in actual size to confirm the fabric ability of the girder. Propriety of design, structural safety, and applicability of the gilder were verified through the load test.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.720-724
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• 2008

The purpose of this study is to evaluate the PM10 removal efficiencies of an Air-washer and an Ultrasonic humidifier by mock-up experiments. The concentrations of PM10 were measured at 5 minute intervals using $\beta$-Ray method. The average PM10 removal efficiency of the Air-washer was 79.8%, while the PM10 concentrations increased with the operation of Ultrasonic humidifier. In the case of operating the Air-washer, the R.H(Relative Humidity) level of the test room was maintained at around 45%, regardless of initial R.H condition. The R.H of the test room with Ultrasonic humidifier was influenced by the initial R.H condition.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1990.10a
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• pp.47-54
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• 1990

Under external loads, large panel structures behave quite differently from monolithic wall structures, because of the distinct planes of weakness in the horizontal and vertical joints between panels. Study on the ultimate load and the failure mode of the large panel structures under extream lateral loads is therefore important. The purpose of this study is to predict the nonlinear behavior of the structure using the general purpose nonlinear computer program 'ANSR' being based on the quasi-static test results of the large panel structure(full scale in two story) and to examine the distribution and change mode of the internal forces which can not be obtained in the test.

• Composites Research
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• v.23 no.6
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• pp.26-31
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• 2010

This research work contributes to a study for the procedure and methodology to assess the fatigue durability for a composite torque link for helicopter landing gear, which was newly developed and fabricated by the resin transfer moulding technique to interchange with metal component. The simulated load spectrum anticipated to be applied to the torque link during its operation life was generated using an advanced method of probabilistic random process, and the fatigue durability was evaluated by the residual strength degradation approach on the basis of material test data. The full scale fatigue test was performed and compared with the analysis results.