Recently, the reduction of energy consumption in buildings and the use of renewable energy become social issues, and an interest in geothermal systems is increasing. In particular, the building integrated geothermal system using has been ground heat e...
Recently, the reduction of energy consumption in buildings and the use of renewable energy become social issues, and an interest in geothermal systems is increasing. In particular, the building integrated geothermal system using has been ground heat exchanger in terms of economy and efficient use of land. Ground-source (geothermal) heat pump (GSHP) systems can achieve a higher coefficient of performance than conventional air source heat pump (ASHP) systems by utilizing the relatively stable underground temperature. The market for these systems in Korea has grown remarkably over the past few years due to efforts to improve the drilling method and reduce the installation cost of ground heat exchanger (for example, utilizing the building pile and foundation as ground heat exchanger. However, it is difficult to optimally design the system due to the absent of quantitative data such as operator data, performance data, so on. In order to predict the performance of horizontal geothermal system using underground structure, this research has developed the method of prediction on the ground heat exchange rate with three-dimension ground heat transfer model. Furthermore, the measurement of underground temperature in basement was conducted to decide the boundary condition of simulation. The result of measurement was compared with it of calculation by the prediction model for the underground temperature. Furthermore, the revised model will be applied to the prediction model of heat exchange rate for the horizontal BIGS.
In this research, the simulation method for a building integrated geothermal system (BIGS) using a horizontal heat exchanger has been developed to couple with groundwater and heat transfer model, ground heat exchanger model and surface heat transfer model. This paper introduces about the summary of the simulation method and describes about the prediction and measurement of surface temperature for setting boundary conditions.
In this results, the heat exchanger rate of ground heat exchange for BIGS system was found as 27.4 W/㎡. using the developed simulation there was still the difference between the calculation result by the revised model and measurement result , but the verification of the prediction model for surface temperature was improved. More detail analysis for the factors of difference will be conducted through the additional measurement and survey.