| Title |
Characteristics Analysis of Seasonal Cold Thermal Storage for Cooling Energy |
| Authors |
Kim, Myung-Rae ; Lee, Ju-Hee ; Yoon, JaeOck |
| DOI |
http://dx.doi.org/10.5659/JAIK_SC.2016.32.11.55 |
| Keywords |
easonal Thermal Storage ; Heat Transfer ; Underground Temperature ; Computational Fluid Dynamics |
| Abstract |
In Korean, the seawater temperature of the Mid-West area in February is less than 3℃ on average, staying unchanged more than 8 days. The seawater cold thermal resource is worthwhile to be used as the stored energy of seasonal thermal energy storage for cooling and heating energy. Regarding hot water thermal energy storage, the countries in Northern Europe commercialize and develop central solar heating plants with seasonal thermal storage. Nevertheless, there is no case of research on seasonal storage and experiment of the heat source for large heating and cooling. Therefore, the purpose of this study is to analyze the temperature characteristics and discharge characteristics of seasonal thermal storage when seawater cold thermal resource is stored into seasonal thermal storage In Korean environmental conditions, and suggest the practical performance and validity of seasonal thermal storage system. A volume of seasonal thermal storage was set to 2,500㎥. As a thermal storage medium, water that features easy purchase and treatment and has large thermal capacity was used. The initial storage temperature of the medium in seasonal thermal storage was 5℃, and its storage period was 130 days. Seasonal thermal storage was buried in the earth, and the earth temperature up to 5m of earth was the earth temperature value observed by Korea Meteorological Administration. For the earth temperature of the more depth, the predicted value calculated by prediction formula was used. The temperature characteristics were analyzed by TRNSYS simulation. The discharge characteristics in the thermal storage were analyzed by CFD simulation. The calculated analysis values and characteristics were analyzed. The 100-days temperature maintenance performance of seasonal thermal storage was found to be 93%, which has almost the same as a German commercial system. Regarding to discharge characteristics of seasonal thermal storage, after stopping in discharge mode, it had immediately stable turbulent motion which was found by CFD analysis. Therefore, it is judged that the seasonal thermal storage for cooling energy is applicable to local cooling or building cooling system. |