• Journal of the Korean housing association
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• v.7 no.2
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• pp.121-129
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• 1996

This study was to estimate how about various effects on the body thermal sensation as air velocity. clo. mean radiant temperature and resultant temperature are varied. The indoor thermal environment elements are measured under the five different of air velocity. Using the above considerations. the following results are obtained. ▶ The states, the air velocity under 0.5 m/s and 0.63 to 0.9 clo. were shown that the comfort zone of mean radiant temperature by 21.2~24.7C, the neutral point by 22.8C, the resultant temperature by 20.7-24.4C and the neutral point by 22.6C. ▶ On equal condition, the draft was occurred at a given air-velocity under 0.5m.s. It was also appeared the floor panel heating system affecting the body thermal sensation by the subject’s below-chest parts and the local discomfort by sensations on the feet and the knees.

• Journal of the Korean housing association
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• v.14 no.5
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• pp.75-82
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• 2003

In this study, the thermal performance of the room control system is analyzed in terms of control performance, potential for coil expansion and energy consumption through experiments comparing the individual room control system and an existing system. The results of this study show that the existing system is not able to supply design water flow rate and does not accurately maintain the set point temperature in each room. However, the individual room control system can set a room air temperature for each room, for it is able to supply design water flow and accurately control the set point temperature in each room and can reduce the energy consumption compared to the existing system. Moreover, the individual room control system can reduce the number of coil division zone and facilitates the construction process, because it can extend the length of the coil division.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.11
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• pp.15-22
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• 2008

This paper presents an innovative prototype of a new conceptual electromagnetic induction heated type far infrared rays radiant heating appliance using the voltage-fed quasi-resonant ZVS-PWM high frequency inverter using IGBTs for food cooking and processing which operates under a constant frequency variable power regulation scheme. This power electronic appliance with soft switching high frequency inverter using IGBTs has attracted special interest from some advantageous view points of safety, cleanliness, compactness and rapid temperature response, which is more suitable for consumer power electronics applications.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.6
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• pp.532-540
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• 2001

The objectives of this study are to analyze the control variables according to condensation occurrence, to find the range in floor surface temperature and frequency of condensation, and to evaluate the control methods through simulations when the radiant heating system is used for cooling. Through the simulation analysis the control methods such as on/off control, variable flow control and outdoor reset with indoor temperature feedback control are evaluated and compared. The results show that the lowest floor surface temperature is around $23^{\circ}C$, the surface condensation can be prevented by controlling indoor humidity within 20g/kg(DA0, and that outdoor reset with indoor temperature feedback control is more appropriate than on/off control and variable flow control with regard to prevention of the condensation and thermal comfort.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.177-180
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• 2012

Korea residential housing generally use wet floor heating system 'Ondol' which consist of insulation cushioning, lightweight foamed concrete, hot water pipe and mortar on top of reinforced concrete slab. Wet floor heating system's installation process is too complicate and difficult to supervise field for continuing assurance quality. Also, this method has a huge impact on the progress of construction because it take a long time to cure finishing mortar and lightweight foamed concrete. Therefore, it is considered a disturbance factor of reduction of construction duration for enhancing competitiveness. In this study, we conducted an experiment about the radiant heat performance and temperature difference on upper panel of rolled dry floor heating systems which is jointly developed by Kolon global and Sumisho Metalex for remodeling housing, studio apartment and the urban-life housing.

• Journal of the Korean housing association
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• v.17 no.2
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• pp.11-18
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• 2006

For the more comfortable thermal environment in residential buildings, it was necessary for variable components like as automatic flow limiting valves and/or balancing valves in hydronic system. And, these components had an effect on flow-rate and pressure inside pipe. In this case, the incompatibility between the design for the heating system and the selection of equipment was the causes of several problems in heating pipe network. In this study, we peformed measurements and analyses of flow rate and pressure inside pipe for radiant floor heating in residential buildings through field surveys and experiments in order to find out the actual conditions and problems. On the basis of this, we suggested the approach for the optimal flow-rate and pressure maintaining inside pipe in individual heating system.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.6
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• pp.375-382
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• 2010

Ondol heating, a kind of radiant floor heating, is a main method used in housing units in Korea. Building energy simulation including ondol and relevant facilities has not been performed due to its complexity. For evaluating energy consumption and indoor temperature variation, a new method should be proposed. At the present work, a dynamic simulation on ondol heating was tried by combining TRNSYS and EES. Characteristic functions for a pump, hot water coils and a gas boiler were simultaneously solved by EES, and calculated flow rates and supply temperature of hot water were provided as inputs of the active layer of TYPE 56 in TRNSYS. The results by the simulation on a typical housing unit in Korea shows a good trend in a viewpoint of actual behavior of ondol heating.

• Proceedings of the SAREK Conference
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• 2004.06a
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• pp.205-205
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• 2004

• Journal of Advanced Marine Engineering and Technology
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• v.20 no.4
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• pp.36-42
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• 1996

Analysis of heat transfer on small-size Diesel engine is required for the development of high performance and efficiency engine. This basic study aims to establish heat transfer technique for marine Diesel engine. The main results from this study are as follows : 1) Overall engine heat transfer correlation of Re-Nu. 2) Radiant heat flux as fraction of total heat flux over the load range of several different Diesel engine. 3) Characteristics of heating curves on piston, cylinder liner and head. 4) Surface heat flux versus injection timing.

• Journal of Mechanical Science and Technology
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• v.19 no.10
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• pp.1950-1956
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• 2005

An analysis has been carried out to investigate the effect of the reflectivity on the temperature distribution of a glass panel by infrared radiant heating. Halogen lamps are used to heat the panel, located near the top and bottom of the rectangular chamber. The thermal energy is transferred from the lamps to the panel only by radiation and it is considered by using view factor. The conductive transfer is limited inside the panel. The results show that the uniformity of the temperature distribution of the panel is improved and, at the same time, the time for heating increases as the wall reflectivity increases. The temperature difference between the center and the corner reaches a maximum in the early stage of the heating process and then decreases until it reaches a uniform steady-state value.