Abstract
A new snow-melting system was developed. This system uses the geothermal energy collected by building piles with circulating water, and is controlled by a snow cover sensor. In the experiment, the snow covered on the concrete-surfaced test section of 20.8m^2 area was melted by the thermal output from two concrete piles of 0.31m inner diameter and 22m length. And it is demonstrated that this snow-melting system operates effectively for the intermittent snow-fall condition in relatively warm areas. Namely, the test section was kept no snow-staying condition during the experimental period (Jan. -Mar., 1991) where we had accumulated depth of snowfall of 187cm and maximum thickness of snow cover of 60cm in Fukui city. The numerical simulation was also made to evaluate the system, where the piles and the heating pipes buried in the concrete-surfaced test section were treated as a connected system. The thermal output from a pile and the heat value collected from the surrounding soils were calculated. Furthermore, temperature profiles of water in the pile were shown for the snow-melting process and the heat recovery process. The comparisons of the numerical results with the experimental ones show good agreement for two examples of different conditions of snow-melting area and flow rate of water in the pile. It is concluded here, that the simulation method described in this paper is useful for designing the said snow-melting system.
