岡山大学農学部
Acta Medica Okayama
0474-0254
41
1
1973
水田の浸透モデルについて(II) 水田一区画を単位とする浸透のモデル化と測定可能量について
79
84
EN
Kinzo
Nagahori
Tooru
Mitsuno
In this paper, supposing that the following equation is concluded, it induces the model of a field lot as a unit in the case of thinking about percolation on large project, and moreover we discuss about some quantities measured in practice. ∂x/∂（R2/1 ∂ｘ/∂H)＋∂y/∂(R2/1 ∂ｙ/∂Ｈ)＋R1/1（H0-H)=0 The results in this paper are summarized as follows. l) In treatment of percolation in the paddy field on large project, the unit is one field lot surrounded with drainage canal. Regarding the one field lot as a unit, physical quantities concerned are q , q1, q2, S1 and S2. We induced the relation among them. 2) Thinking" about the vertical section crossing drainage canal in the two dimension, the apparent model indicating" the motion of percolation water in that vertical section is shown in the Fig. 2, and moreover it is transformed to equivalent model shown in the Fig. 4. Parameters indicating the characters of this model are R and RH, or R' and RH'. 3) This model is induced from the start-point of equation (1) concluded in the macro soil model. And then, in the two layer geometrical model L/D=5, D/d=4, as the result of comparing Darcy's dimensional solution with this model in the case of k2/k1=1 and k2/kl=20, both are not very good consistent in the case of k2/k1=1, but are fairly good consistent in the case of k2/k1 = 20. From this result, it may be considered that the propriety of applicable extent (k2/k1 > 10) for the macro model could be proved. 4) The quantities measured in practice are q , S . S1 and S2, and parameters included in the equations should be calculated back from these quantities.
No potential conflict of interest relevant to this article was reported.
岡山大学農学部
Acta Medica Okayama
0474-0254
40
1
1972
水田の浸透モデルについて
97
106
EN
Kinzo
Nagahori
Tooru
Mitsuno
To prove the relation between the increase and decrease of the percolated water quantity in the paddy fields around the lake due to the variation of water level of the lake, we first noticed that not only the physical character of the soil but also the character of soil layers structure were greatly concerned in the phenomena of percolation in the soil under the paddy fields, and in case of thinking of this matter, mentioned the idea of the porcolation water model through down from the paddy fields. Moreover, establishing the simplest two-layer structure model, we examined applicable state of Darcy's law and treatment of the macro model, and verified the propriety of treatment of the percolation water model under consideration of the condition of soil layers. In short, these results are as follows. l) When we considered the macro model, we supposed the imaginary water level H in the case of combining vertical percolation and horizontal direction. In the Fig. 3, as a result of comparing H with h from micro viewpoint, we found that H was nearly equal to the averaged value of h in the vertical direction. 2) When we examined qx in the Fig. 4, we found the following thing. When the value of k2/k1 is smaller than 10, the calculated value is in bad agreement with the measured one. On the other hand, as the value of k2/k1 becomes larger than 10, the calculated is in better agreement with the measured. 3) As we could find in the Fig. 5, it became clear that the calculated value was in fairly good agreement with the measured in the geometic model used here when the value of k2/kl was larger than 10. In the actual paddy fields, the value of L/D is lager. Therefore, it may be thought that the stream of the under layer more approaches to the level stream, and the agreement is further better. 4) By the electric model and approximate calculation, we examined the relation between S2/S1 and q R1/S1 under the condition of k2/k1=20. In consequence, judging from that straight relation between them comes into existence and one is in fairly good agreement with the other as showed in the Fig. 6, it may be thought that the propriety of establishment of macro percolation water model is verified.
No potential conflict of interest relevant to this article was reported.