• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.24 no.6
• /
• pp.509-514
• /
• 2012

In this research, a heat pump system with a heat source network is suggested which utilizes solar heat and ground heat as heat source for cooling and heating. This paper describes the summary of the suggested system and the results of the annual energy simulation. The heating and cooling loads, the electric consumption and the COP were calculated by TRNSYS 16 and evaluated in the cases of different local conditions and different system compositions. In the results, the superiority of the suggested system has been quantitatively evaluated comparing with the conventional heat pump system using one heat source. Furthermore, it was more significant in cold climate, in which the heating COP was 146% increased compared the air source heat pump system, than it in subtropical climate, 119% increased.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.24 no.4
• /
• pp.289-296
• /
• 2012

The aim of this study is to investigate the performance of a heating and cooling system with aquifer thermal energy storage(ATES heat pump system) known as one of the underground thermal energy storage application systems. The ATES system was composed of heat pump unit and ATES, which was installed in a factory building located in Anseoung. The system represented very high heating and cooling performance, and showed nearly constant COP at each heating and cooling season due to the stability of EWT. The economic analysis about an ATES system and a conventional system was also executed. The conventional system adopted an air-conditioner in the summer season and a LNG boiler in the winter season. The payback period of the ATES system was estimated by 6.62 years.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2013.11a
• /
• pp.234-235
• /
• 2013

Recently, interest in renewable energy is rising in rural areas in order to reduce heating and air-conditioning costs which are directly connected to farmhouse income. Thus, in this paper, I study renewable energy supporting projects in rural area: I analyze distribution of the Agriculture & Fishery Energy use Efficiency Project and 1 Million the Green Homes program by using project performance data and the data of Korea Energy Handbook. The results of my analysis of the two programs show that, while annual average increase of the 1 million Green homes prgram is 15.6%, the distribution rate of heating and air-conditioning facilities using geothermal heating and cooling system of the project has decreased by average 37% every year.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
• /
• v.3 no.3
• /
• pp.185-190
• /
• 1974

Floor panel heating system is popular in Korea as dwelling house heating system. There are two methods for keeping floor surface warm. One method is delivering warm air under the floor such as Roman Hypocaust and Korean traditional Ondol. The other method is imbedding hot water pipes into the concrete floor slab. This paper gives basic equations for steady and transient solutions of heat conduction from hurried pipes. For steady-state solution, fin Efficiency Method and Sink and Source Method were introduced. Sink and Source Method is applied to transient state and basic solution is given in the form of Exponential Integral Function. Numerical solutions can be solved easily by digital computer from these equations.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
• /
• v.12 no.1
• /
• pp.2-11
• /
• 1983

The solar energy retention rate of a flat plate collector can be increased by increasing water flow rate through the collector which also increases the pumping energy incurred in obtaining that solar energy. The problem of optimal flow rate is formulated to fit within the framework of pontryagin's maximum principle and with a few simplifying assumptions, an optimal solution that can be easily implemented is obtaincd, The optimal solution is used in the simulation of a solar heating system using actual climatological data and the results are compared with that of on-off control. The result that not only the object function but, In some cases, also the solar energy retention rate the collector is increased. In is also found that the optimal control gets more advantageous as the solar insolation level gets lower, and also as tile cost of auxiliary heating fuel gets higher.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
• /
• v.15 no.3
• /
• pp.292-298
• /
• 1986

The new f-chart capable of estimating long-term thermal performance of solar space and water heating systems was developed. The system comprise a flat plate solar collector, heat exchanger, storage tank filled with water, auxiliary fuel fired heater, and a house structure. The information obtained from many simulations of solar heating systems has been used to develop this f-chart. Actual hourly meteorological data collected in Seoul, Daejeon, Kwangju and Daegu, Korea from 1979 to 1983 have been utilized in these simulations. The new f-equation is as follows: $$f=1.034Y_{-}0.0968X_{-}0.2235Y^2+0.0043X^2+0.0144Y^3$$. The system performance estimates obtained from the developed f-chart are in close agreement with the results of experiment.

• Proceedings of the SAREK Conference
• /
• 2009.06a
• /
• pp.650-655
• /
• 2009

In this study, a consumer willingness to pays for residential heating systems are estimated by economic valuation method. The major Korean residential heating systems in apartments are central heating system (CH), district heating system (DH), and individual heating system (IH). However, DH and IH systems are adopted in newly constructed apartments. Each heating system has own characteristics which residents can identify and value. 700 households in apartment were surveyed to analyze the preference of the residential heating systems and to estimate willingness to pay. We find that the households in DH system are more satisfied with their heating system than the households in other systems overall and that consumers prefer an apartment with DH system than with IH system and the willingness to pay for IH system is less than DH system. The results indicate that DH system has the relative premium which may be caused by the safety and the convenience to manage the system.

• Proceedings of the SAREK Conference
• /
• 2005.11a
• /
• pp.121-128
• /
• 2005

This is about experimental comparison study between convective heating and radiation heating system to use the design criteria for residential house. Experiment was done in EC(environment chamber) under simultaneous outdoor condition for 4 kinds of heating system such as CRHP(Ceiling Radiant Heating Panel), BEHC( Bottom Electric Heating Coil Mat), EFCU( Electric Fan Coil Unit) and CEHU( Convective Electric Heating Unit). Result show that CRHP ,which is radiation heating system, can consume more 23% energy than convective heating system when it is operated by dry bulb temperature but can save 1 ${\sim}$ 10% when operated by glove temperature and 27% when operated by MRT.

• Proceedings of the SAREK Conference
• /
• 2008.11a
• /
• pp.381-386
• /
• 2008

In this study, the energy characteristic of automatic thermostatic valves according to each heating method in floor radiant heating system were researched by computer simulation. For the analysis of unsteady heat transfer phenomena in household, the method of using electrical equivalent R-C circuit is applied, and radiation heat transfer between panel, ceiling and walls in household is calculated by enclosure analysis method. The parametric study on heating method, valve's control method, outdoor air condition, supply heating water temperature, supply flow rate are performed to compare energy characteristic, respectively.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.13 no.5
• /
• pp.363-363
• /
• 2001