Vízügyi Közlemények, 1947 (29. évfolyam)

1-4. szám - VI. Szakirodalom

(15) II. BASIC PRINCIPLES OF STORAGE. 1. Essence and Aims. The aim of storage is to adapt the natural flow to the needs of consumption. We distinguish lowland and mountainous storage. Streams can be stored in their own beds or in the valley of any of the neighbouring streams having more favourable topographical conditions. The different cases of storage are explained by examples given by the author. 2. Elements of Reservoirs. According to usual division reservoirs consist of two parts, which are: the dam and the basin. From hydrological point of view reservoirs have also a third essential component part and this is the drainage area. The perfect solution of storage often, requires work, such as forestation, consolidation of washes and dam to keep up sediment etc. in the drainage aerea. 3. Useful Capacity of Reservoirs. Figure 1 shows the parts of the storage area. These are: undrainable part (5) and drainable part (

4

) of the useless area, reserve area (3), useful area (2), useful area for flood control (

1

), security for unexpected floods (0). In the forthcomings, owing to lack of a separate term, by "capacity" the useful part of the reservoir will be meant. The aforementioned parts of reservoirs are separated by characteristic water levels. 4. Output of Reservoirs. By the degree of utilization for a reservoir A. LUDIN means the ratio of yearly utilized water quantity to the (useful) capacity of the reservoir: V average value of which, relating to n years, is given in Formula (2). For absolute output of reservoirs the author does not take the above index, but the mean discharge which is equivalent to the water quantity steadily available according to given needs of consumption [s (i)] • This may be called average consumption or utilizable mean discharge (/* m

3/sec). In case of consumption of given character [e = s (i)] there belongs to each capacity a different value of the average consumption: S = Ф (fii). The relative output of a reservoir may concern two possibilities. If comparison of different reservoirs be aimed at, relative output is indicated by the index: (3) i = - m

3/

se

c S ' ' hm

3 which is closely connected with the above mentioned LUDIN factor. However, it may happen that output of a reservoir is compared to the output available through maximum storage possibility in the very same dam sits. In the forthcomings the possible maximum output, i. e. the maximum average consumption will be explained, which is characteristic for a certain section of the river (Sign: Qk m

3/sec). So relative hydrological output relating to any dam site may be indicated by the ratio of: !Л\ /* (4) 1,1 = By this an undimensional figure is resulted which, after Formula 4'

, is explicable in percentage as well.