The Study on Efficiency Improvement of a Thermal Storage Tank for Solar Combined Heating System

태양열원 난방기의 수축열조 효율개선에 관한 연구

  • Ryu, Nam-Jin (Kangnam Co., LTD.) ;
  • Han, Yu-Ry (Department of Mechanical Engineering, Cheju National University) ;
  • Park, Youn-Cheol (Faculty of Mechanical Energy and System Engineering, Cheju National University)
  • Published : 2007.12.30

Abstract

This study is conducted to improve the efficiency of a thermal storage tank. The thermal storage tank was designed to store heat energy that obtained from the solar or the others heat sources. However, it has difficulties in storing heat with nonuniform temperature through the entire tank with respect to the vertical direction, This study is focused on the thermal stratification to improve thermal comfort for the resident in house. To enhance temperature stratification of the tank, a distributor was designed and installed in the middle of the storage tank vertically. The vertically designed distributor could supply the return water with stratified temperature in the storage tank with respect to the height. The water velocity from the distributor hole is the same with the other outlet in the distributor. However, gravity effect on the flow in the storage tank is much higher than that of the velocity effect due to that Froude Number is less than 1. During the heat charging process in the storage tank, temperature maintained with little difference with respect to the height. However the charging process takes long time to get a effective temperature for the heating or hot water supply because of all of water in the storage tank needs to be heated.

Keywords

References

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