| Project/Area Number |
03660239
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
農業土木
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| Research Institution | THE UNIVERSITY OF TOKYO |
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Principal Investigator |
SHIOZAWA Sho THE UNIV. OF TOKYO,Fac. of Agric., ASSISTANT PROF., 農学部, 助手 (80134154)
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| Project Period (FY) |
1991 – 1992
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| Project Status |
Completed (Fiscal Year 1992)
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| Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1992: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1991: ¥1,500,000 (Direct Cost: ¥1,500,000)
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| Keywords | soil moisture movement / temperature gradient / hydraulic conductivity / matric potential / 温度勾配による土壌水の移動 / 不飽和透水係数 / 水分特性曲線 / 土壌物理学 |
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| Research Abstract |
Although the physical governing equations that describe the soil water movement under temperature gradients have been known, it is hard to simulate the transport phenomena because of the difficulty of getting the soil physical properties included in the equations. Most of the properties depend strongly on moisture contents. The goal of this study to simulate the water movement under temperature gradients. The hydraulic properties of the Sand Dune Sand were measured conducting several experiments. The main experiments in this study is of the water movement in closed soil column with temperature gradients. The changes in water content profiles, NaCl concentration profiles in the soil columns were measured. The analysis of the experimental data gave the coefficient of water vapor movement due to temperature gradients as the function of water content. The coefficient of beta, the ratio of water vapor diffusion in air and in soil, is small at low water content, but is up to 1.5 at higher volumetric water content than 0.04. Expressing the physical transport properties as the functions of water content and temperature, the numerical solution to the partial differential equations governing the transport phenomena were obtained. The calculated water content profiles were similar to these observed.
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