Vízügyi Közlemények, 1948 (30. évfolyam)
2. szám - VII. Szakirodalom
(9) (Figure 60). If, from Formula (11) of the storage curve, the m height expressing fluctuation of the storage level can be developed as a function of capacity as given under (93), our differential equation reads as follows: L a ds (94) q(t) ^ = -. I dt c 0s" + M Owing to mathematical complications in the general solution it is more convenient to use the graphical method in our proceedings. b) Seasonal Reservoir. Studies into seasonal reservoirs can be made in principle on the basis of what has been said in the former Chapters about this topic. Substance of the problem and the way of solution are explained in Figure 61. c) Reservoir For Total Utilization. We can speak about a reservoir for total utilization, when in a certain drainage area non-loss utilization of a long period (several decades) total run-off is aimed at. In this case it is obvious that mean consumption and average annual mean discharge (its ideal value) show no difference whatsoever. Between annual and total utilization reservoirs we have the multi-annual reservoirs wich serve utilization of mean discharges of some more or less long, but always several years periods. Figure 62 explains computation of storage capacity for a multi-annual reservoir. d) Relation Between Output And Capacity. General form of the storage characteristic is shown in Figure 63. This diagram is essentially identical with that of uniform consumption but it must be pointed out that the ordinates here stand for no effective consumption but for the mean values of consumption. Section between S Q and SQ of the curve consists also in this case of flat arches joined fractionally. e) Small Reservoirs. (Pondage.) Daily and weekly storage differs somewhat from all that has been said about equalization, viz. here we hâve a discharge of no or only of little fluctuation and a consumption of largely variable character. As study of pondage is not included in the author's sphere of investigation, he does not go into details with this problem. In Figure 64 basic conception of design is shown. V. NECESSARY CAPACITY FOR PERIODICAL CONSUMPTION OF DEFINITE CHARACTER AND INTENSITY. Periodical consumption, too, may be of 1) uniform or of 2) variable intesity. Using either the graphical, or the mathematical procedure, computation of storage capacity does not differ in essence from the aforementioned methods. Periodical consumption may be described as a special case in steady consumption of variable character where from time to time the character-function s (t) takes the value of zero. An example for annual storage is given in Figure 6,5.
