貯留時間による調整池容量の検討

• 広瀬 慎一

  富山県立大学短期大学部農業技術学科

書誌事項

タイトル別名

• Determination of the Capacity of a Regulating Pond in Terms of the Discharge Average Multiplied by <I>n</I> Hours
• A study on an irrigation system consisting of a regulating pond and pipelines (IV)
• 調整池とパイプラインによる水田潅漑システムの研究 (IV)

抄録

This paper is the fourth of a series of reports on the pond-regulated pipeline irrigation systems in operation in Tonami Plain of Toyama and deals with some central aspects of these systems that previous papers did not address.Analyses of the observation data on three of the systems obtained over an eight-year period have yielded the following findings:<BR>(1) Out-of-pond discharges (Q_fi) usually peak between 6 and 7 a.m.and/or between 7 and 8 p.m.The maximums of Q_fi during the morning peak hours often far exceed the maximum gross water requirements for the ordinary irrigation period (q).<BR>(2) Pond uses (Q_po), which are meant to compensate for the excesses of Q_fi over inflows into the ponds (Qin), are devoted for the most part to morning irrigation in keeping with the peaking of Qfj.<BR>(3) Data on Q_in, Q_fi and Q_po, graphically plotted, show that there are three patterns in how they are related to each other, i.e.morning peak type, two-peak type and evening peak type.<BR>(4) Let us define T_po as a per-day discharge excess over the discharge average (avr, Qfi), calculated in terms of the discharge average multiplied bynhours and for convenience expressed simply asnhours.Then we obtain a formula V=T_po·avr QM where V stands for the design capacity of a regulating pond.<BR>(5) I chose the 10 topmost of per-day Q_po and averaged out the T_po values for these Q_po data. These T_po averages range from 3 to 6 hrs. Since they reflecting the actual demands of the benefited paddies, they can be expected to be optimal design criteria for pond capacities.<BR>(6) The smaller the acreages of the benefited paddies (A), the greater are the T_po values. Besides, as I pointed out in my previous paper, the smaller the acreages, the greater are the values of Q_po/Q_fi. These facts suggest that the T_po value of 6 hrs, which was obtained in the smallest pond-regulated irrigation system can be regarded as the safest capacity for a regulating pond.<BR>(7) The foregoing consideration of T_po would allow us to draw the following conclusion: since the actual T_po values range from 3 to 6 hrs, the values of T_po in the formula V=T_po·avrQ_fi should be determined within this range and since, as I reported in my previous paper, the maximums of pond uses are concentrated between the latter half of July and August, the value of avr Q_fi should be pegged atqfollowing a generally accepted criterion for irrigation facilities. Needless to say, in determining the values of T_po, we need to take into account several related factors, such as the characteristics of water sources, the meteorological conditions of the areas concerned and the characteristics of benefited paddies including, importantly, their acreages. We now know that, the smaller the acreages, the greater are the T_pos. At any rate the T_po value of 6 hours can be regarded as a safe enough criterion for determining the design capacities of regulating ponds.

収録刊行物

• 農業土木学会論文集

  農業土木学会論文集 1995 (175), 37-45,a1, 1995

  社団法人 農業農村工学会

キーワード

• 貯留時間
• 調整池容量
• 潅漑の自由度
• 調整池水収支
• 調整池潅漑システム
• 普通期最大用水量
• 調整池有効利用量

詳細情報

• CRID: 1390282679518043904
• NII論文ID: 130004118723
• DOI: 10.11408/jsidre1965.1995.37
• ISSN: 18847234
• ISSN: 03872335
• データソース種別:
  • JaLC
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可