• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.23 no.3
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• pp.299-309
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• 2014

When using an automotive heating, ventilation, and air conditioning (HVAC) system, we can obtain fresh outside air while maintaining the interior vehicle temperature. In this study, a correction equation considering experimental data for automotive indoor air leakage is defined to simulate the ratio of fresh air to recirculated air in the automobile cabin. With this correction equation, numerical results are compared with experimental data and validated. The $CO_2$ concentration in the automotive cabin is evaluated by considering various boarding conditions and mass flow rates of the HVAC system. The $CO_2$ concentration model derived in this study is expected to be used to control the effective air conditioning and become a basic research tool for automotive air quality control system development.

• Journal of odor and indoor environment
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• v.17 no.4
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• pp.303-314
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• 2018

The urban railway system is a convenient public transportation system, as it carries many people without increasing traffic congestion. However, air quality in urban railway environments is worse than ambient air quality due to the internal location of the source of air pollutants and the isolated space. In this paper, characteristics of particulate matter (PM) pollution in urban railway environments are described from the perspective of diurnal variation, chemical composition and source apportionment of PM. PM concentrations in concourse, platform, passenger cabin, and tunnel are summarized through an analysis of 34 journal articles published in Korea and overseas. This information will be helpful in developing effective policies to reduce PM pollution in urban railway environments.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.2109-2113
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• 2008

As the standard of living is higher, the passengers using public transportations desire better qualities of environment as well as more comfortable indoor environment. In case of train, the passengers' comfort in passenger cabin is one of the most important elements to be competitive with other transport systems. The indoor air quality of the cabin should be managed properly, because many passengers travel for a long time in the small space of $144\;m^3$. For proper management of the air quality, the heating, ventilation and air conditioning (HVAC) system is required for the ventilation of the compartment. To maintain comfortable environment in the compartment, the automatic ventilation system is needed to exchange the indoor air with fresh air or clean indoor air. In this study, we investigated the indoor air quality (PM-10, $CO_2$, and VOCs) in the compartment of train. In addition, type and pattern of PM-10 has been analyzed through the clustering analysis. Based on the analysis, we could found that the fine particulate matters in the compartment can be a serious hazard to human. To control the concentration of PM-10 and $CO_2$ air cleaners were developed. Through this study, it is expected that people who take a train will be in a more comfortable environment.

• International Journal of Air-Conditioning and Refrigeration
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• v.15 no.4
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• pp.147-155
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• 2007

Mobile air conditioning systems work under widely changing operating conditions. To understand the system behavior under such dynamic conditions, a test facility that can impose transient loads as well as conducting dynamic measurements is needed. To test mobile air conditioning systems including their dynamic performance under various drive cycle patterns without using full scale vehicles in a wind tunnel, a new test facility, called "dynamic simulator," is described. It can replicate real vehicle operating conditions by interacting with the system being tested based on the measured system performance and subsequently adjusting the air properties returning to the test system based on the results of a numerical cabin model. A new dynamic simulator has been designed, constructed, and verified for performing dynamic tests. It was successful in controlling the temperature and relative humidity of the air returning to the test unit within ${\pm}0.7^{\circ}C$ and ${\pm}4%$ of their respective intended values. The verification test under the New European Driving Cycle demonstrated that detailed transient behavior of the mobile air conditioning system could be measured by using this dynamic simulator.

• Journal of the Korean Society for Railway
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• v.11 no.2
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• pp.182-187
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• 2008

The environmental significance of indoor air quality is gaining more attention. Especially, the contamination of indoor air by volatile organic chemicals (VOCs) has become a serious environmental concern. We investigated the VOCs emissions from some interior materials used in the conventional railway passenger cabin. The seat cover and the flooring of cabins were used as testing materials, and they were put in a clean environmental chamber. The temperature and relative humidity was kept at $25{\pm}1^{\circ}C$ and $50{\pm}5%$, respectively. It was found that these interior materials emitted significant amount of VOCs under constantly ventilated condition. The flooring emitted more halogenated VOCs than the seat cover, because it is made of PVC, which contains many chlorine atoms. However, the emission gradually decreased over time. Because the VOCs emission from interior materials may threaten the health of passengers in the cabin, interior materials emitting less VOCs should be used.

• Proceedings of the Acoustical Society of Korea Conference
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• 1994.06a
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• pp.860-863
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• 1994

Main sources of increased vibrations and air noise on ship are main and auxiliary engines and ship ducts. The various ways of transfer of vibration energy and air noise in passenger cabin of a vessel require, in general case, of various methods of attenuation. The transfer of vibration energy from engines through a support requires, alongside with shock-absorbers, availability active shock-absorbers. The transfer of vibration energy and hydrodynamic noise on ship ducts requires availability, alongside with flexible muffler, active mufflers. The availability of air noise from working equipment can require, along with absorbent covers, of space systems of active noise control. In the given article it is spoken about the unified approach to formation of the block-diagram of active noise and vibration control. The complex approach permits to receive additional efficiency in reduction of noise in passenger cabin of vessels.

• Journal of Advanced Marine Engineering and Technology
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• v.32 no.5
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• pp.717-723
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• 2008

The purpose of this study is to measure and analyze the indoor thermal conditions of a 8,500GT class chemical carrier which was launched on July 2007. The measurement was operated from 4th June to 4th June 2007, just before handing over to Owner. Followings are the results of this study. (1)The temperature variations of supply air were related to the outdoor temperature variations, but the humidity was stable at $65{\sim}80%$. (2)The temperature variations at the representative position of bridge, restaurant, crew's cabin showed gentle slopes. but that of conference room was very steepy. The humidities of bridge and restaurant were unstable because of outdoor-contact and cooking, respectively. (4)The temperature and humidity of ECR(Engine Control Room) which was designed to supply heating and cooling by PAC(Package Air Conditioner) were directly affected by the operating conditions of PAC. (5)The measured supply air volume from dampers of bridge, crew's cabin and conference room were satisfied with the design supply air volume. (5)For the improvement of the indoor thermal conditions, the temperature of crew's cabin and restaurant and the humidity of conference room, and the temperature and humidity of bridge should be controlled, respectively.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.568-573
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• 2011

Carbon dioxide concentration of railroad passenger cabin is obliged to be kept lower than guideline values of 'Indoor air quality guideline for public transportations', but actual carbon dioxide concentration frequently exceeds this guideline value. Ventilation is most desirable to lower carbon dioxide concentration but there are some cases when the ventilation is not applicable. In this study, carbon dioxide concentration control method using adsorbents was presented. The cation of zeolites were exchanged with various kinds of cations, and the carbon dioxide adsorption performance of the zeolites were studied. The various kinds of cations, solvents, and zeolites were introduced, and it was found that some cation-exchanged zeolites showed good carbon dioxide adsorption performances. It is expected that the obtained results will be used to lower carbon dioxide concentration of railroad passenger cabin.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.138-141
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• 2011

Carbon dioxide concentration of railroad passenger cabin is obliged to be kept lower than guideline values of 'Indoor air quality guideline for public transportations', but actual carbon dioxide concentration frequently exceeds this guideline value during the morning and evening rush hours. For improving comfortability and satisfaction of passengers, concentration control method using $Al_2O_3$ adsorbents was presented. The adsorbent is made from $Al_2O_3$ and LiOH. $Al_2O_3$ perform as a frame and LiOH as a chemical adsorbent. The adsorbent performance experiment was carried out by measuring concentration change of Carbon dioxide in terms of flow, initial concentration and amount of adsorbent. It is expexted that the obtained results will be used to lower carbon dioxide concentration of railroad passenger cabin.

• 한국전산유체공학회:학술대회논문집
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• 2001.10a
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• pp.31-36
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• 2001

The velocity and temperature profiles in the cabin of the automobile affect greatly to the comfort of the passenger. In this paper, the three dimensional flow and temperature analysis in the cabin of the automobile which is geometrically complicated was performed to investigate and predict the velocity and temperature profile. The three dimensional Navier-Stokes code used in this case was validated by performing of a 1/5 experimental scale model vehicle flow anal)rsis successfully. The temperature field of cavity was analyzed for Energy-equation code validation. The comparison of the results are made with the polished computational data and give a coincided one.