• Journal of the Korean Society for Railway
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• v.10 no.1 s.38
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• pp.67-73
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• 2007

Experiments were carried out to investigate smoke movement in platform of a subway station which currently is in service in Pusan, the second largest city in Korea. The recently constructed underground station of the "bank type" (two platforms on both sides of track) which is the popular layout of platforms in Korea, is chosen in Pusan. The smoke generator and heater are used for simulating the smoke movement at the fire break in the platform located in the 2nd basement of the station. Video recordings were used to monitor smoke lowering. In this study, the movements of smoke in the underground station are investigated under various smoke-control operating modes. Three tests wire conducted according to its operating mode of the ventilation systems in the platform: no operation of any ventilation systems, smoke extraction mode in occurrence of fire (presently running mode) and full capacity of smoke extraction where all vents are activated in the platform. The results can be used for comparing with the numerical prediction results of fire subway stations.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.3
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• pp.37-42
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• 2008

This study is focused on the numerical predictions for different smoke-control ventilation modes for the subway fire. Smoke-control ventilation mode in the domestic platform is that exhausting for the smoke detected zones while supplying air or stopping any ventilation for other zones in the platform. Three cases of smoke control ventilation modes are considered. First and second case are present running smoke control mode in Korea. The third is that smoke-control ventilation fans equipped in the platform are operated in first 4 minute(platform evacuation time, NFPA130) since then the fans equipped in the platform are stopped and the fans equipped in the tunnels are operated. Distributions of heat, carbon monoxide and visible range are compared at a height of 1.7m(passenger breath/sight height) above the platform. The numerical results show that air supply fan operation in the platform causes the smoke disturbance and a rapid spread of the smoke. The switch-operation with fans in both the platform and tunnel are better than operation with only platform fans in smoke rejection efficiency.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.1307-1312
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• 2007

This experiments are performed to investigate the effect of ventilation velocity on a high pressure water mist fire suppression in subway train. The experiment is conducted in half scale modeled train of a steel-welled enclosure (8.0m*2.4m*2.1m). The ventilation velocity is controlled by the ventilation duct through an inverter in the range of 0 to 2 m/s. The coverage-radius and an injection angle of an high pressure water mist system are measured. The mist nozzle with 7-injection holes is operated with pressure 80 bar. The heptane pool fires are used. The fire extinguishment times and the temperatures are measured for the ventilation velocities. In conclusion, because the momentum of injected water mist is more dominant than that of ventilation air, the characteristics of water mist, the fire extinguishment times and the temperatures are affected very little by ventilation velocity.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1970-1974
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• 2010

This paper is how to improve contaminated air by the pollutant from vehicles through ventilators and entrance at the underground station. We are looking for the environment management to take care of customers. There is two ventilation systems. One is natural ventilation system, the other is forced ventilation system. Usually, subway ventilators were installed low on the sidewalk. There are lots of craps on the ventilators, so these things interrupt influx of outside air. But the gas from the vehicles comes into the station through entrance. There is lots of noise while ventilations run. So we install the supply air vents away from the road for the customers. If it's difficult, we cover around the ventilator with clear plastic plates more than 2M heights. We also install silencer on the ventilators. We install the air curtains on the entrances to prevent dust from outside. Seoul Metropolitan has a plan to make 60M deep underground road. To improve underground road air quality, ventilators should be installed that consider the above information.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.6
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• pp.695-701
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• 1998

Researches on unused energy are being continued because of the limited fossil fuel and the destruction of environment. Therefore this study was peformed as follows. The collectable amount of exhausted heat for an air-conditioning was calculated by the subway thermal environment prediction program. And the electric power needed by conventional heat source equipments was compared with one by unused heat source equipments when the exhausted heat was used by heat pump in heating and hot water supplying. The results are summarized as follows; 1) Forced ventilation should be conducted to keep optimal temperature in subway tunnel in summer as well as in winter. According to the simulation, temperature in tunnel was higher than that on the ground in summer when the forced ventilation was conducted only in winter. 2) Ventilating time should be calculated out to the optimal condition for not only saving power of ventilation fan but reusing exhausted heat. By the simulation, it is certain that the exhausted heat should be eliminated in air-conditioning time. 3) The use of exhausted heat source heat pump could save 8% of electric power per hour in comparison with existing heat pump. It was based on a present heat generation and traffic for ventilating time of general air-conditioning, but could be different by ventilating time. 4) As the traffic increases up to 1.5 or 2 times, electric power consumption of the conventional heat pump increases to 11% or 13.5% per mean hour in comparison with that of the exhausted heat source heat pump, though all-day ventilation.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.3
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• pp.353-362
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• 2015

Platform screen door (PSD) installed at underground subway station has reduced the safety accident, but it may cause poor air ventilation condition due to the isolated exhaust duct in the subway tunnel area. In this study, the additional ventilation system was suggested, which can be installed at a void space (i.e., storage room under stairs) of platform in order to improve efficiency of air ventilation rate. Exhausted air from platform was directed to underneath of platform and joined with existing ventilation duct of train exhaust system (TES). One subway station in Seoul city was selected to predict the effectiveness of the suggested lower exhaust system by using the computational fluid dynamics (CFD) analysis. The predicted mean age of air was decreased by 16.5% which proves the improvement of air ventilation efficiency when the suggested lower exhaust system was applied.

• Explosives and Blasting
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• v.9 no.2
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• pp.8-12
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• 1991

The Land price in Tokyo Vicinity was, increased 65.3% than Last year. so, it trend to get Subway constructed in deeper Underground. But, the subway Construction Cost is more increaseel beeause it is needed long works term, all modernized facilities beside that, deeper subway cocstruction works brought another task such as deeper entrance shaft sinking, Ventilation escapeway, all Underground water Treatment. In addition, Civil Act must be also amended became at Present landowner covers ground and Underground.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.157-160
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• 2010

Management of indoor air quality of underground subway station is an important issue since the limited natural ventilation, limited sunshine incoming, and highly moistured atmosphere. The improvement in IAQ of platform is expected because most stations were installed with platform screen door currently, however, the poor air quality in tunnel might be affecting subway cabin indoor. In this study, we developed the air quality assessment model based on computational fluid dynamics. The geometry of air ventilation unit, seat, LCD monitors, and passengers were modeled using commercial software (Design Modeler) and fluid pattern and pollutants trajectories were analyzed by using CFX. We predicted the thermal comfort by predicted mean vote (PMV), distribution of CO2 and PM10 concentration. It is expected that this model can be used for the performance test of air cleaners which are under development.

• Proceedings of the KSR Conference
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• 2001.05a
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• pp.139-146
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• 2001

Modern people stay at indoor places about 90% of a day. Radon-222 is a gas produced radioactive decay of the element radium. And, radon is one of the major indoor air pollutants moves into the underground space through various routes and is considered to cause lung c hurting the lung tissues, In this study, we measured the subway radon level at 9 stations o According to test results, we can figure out the concentration of radon by lines, times, and m points. So, it was found that ventilation conditions are the most important factors in the su quality. Finally, we suggested effective and economic management methods of air pollution subway.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.537-540
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• 2008

A numerical study has been carried out on the optimization of an air cleaning system which was installed in a heating, ventilation and air conditioning system (HVAC) system of subway station for particle removal. Required particle removal efficiencies of three different air cleaning systems were calculated from ventilation rate, and indoor/outdoor concentration of PM10. Mass balance equations of PM10 were used to solve the required particle removal efficiencies. Fibrous filter was considered as an air cleaning system. Calculations were carried out about two different places which were waiting area and platform of subway station, respectively. This study proposed optimized design and operation condition of each air cleaning system.