NAGAI Niro University of Fukui, Department of Mechanical Engineering, Associate Professor, 工学部, 助教授 (70251981)
MIYAMOTO Shigenobu Fukui Prefecture, Snow Management & Construction Technology Research Center, Head Researcher, 建設技術研究所・総括研究員
加賀 久宣 福井県雪対策, 建設技術研究所・研究員
|Budget Amount *help
¥2,700,000 (Direct Cost : ¥2,700,000)
Fiscal Year 2004 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 2003 : ¥1,200,000 (Direct Cost : ¥1,200,000)
Fiscal Year 2002 : ¥1,000,000 (Direct Cost : ¥1,000,000)
Simulation software was developed for simulating geothermal snow melting system using foundation piles. The snow-melting model is based on thermal energy balance among snow-melting pavement road surface, piles, soil, dissipation pipes and etc. The software can simulate situations of melting snow and remaining snow on road surface, storage of thermal energy into soil, and etc. It is also applicable to the system with multiple piles, where the many piles are arranged in lattice configuration such as foundation piles of bridges. For simulating snow melting on road surface, temperature distribution inside snow layer is also considered so that the software can apply to snow melting situations for frigid regions such as Tohoku and Hokkaido district.
Input data for the software are as follows : dimensions and arrangement of heat collecting and heat storage piles, constitution of soil, dimensions and structure of pavement road surface, dimensions and arrangement of dissipation pipes, kinds and
flow rate of heat medium, meteorological data such as rainfall including snowfall, air temperature, wind velocity, humidity, solar radiation, sky radiation and etc. Output data from the software are as follows : situations of melting snow and remaining snow on pavement road surface, mean temperature of heat medium inside piles, mean temperature of pavement road surface, transferred heat, operation time of circulation pump, and etc.
Field tests of this snow-melting system have been conducted at Nakamaizuru pedestrian bridge, road surface inside Research Center in Fukui city and test road surface in Sapporo. The simulation results are in good agreements with these field tests results, that show validity of the simulation software developed in this research.
In addition, the simulation demonstrated possibility of thermal storage during seasons using multiple piles with appropriate pitch, where stored heat inside soil in summer does not dissipate so much that the heat can be applied to snow-melting operation in winter. This thermal storage during seasons was experimentally confirmed and utilized to design of Shin-Kiyonaga bridge under construction. Less