Vízügyi Közlemények, 1996 (78. évfolyam)

2. füzet - Starosolszky Ödön: Gondolatok a hidraulika modellezéséről

Gondolatok a hidraulikai modellezésről 171 — For movable-bed scale-models: — Appropriate channel-bed material should be selected for assuring similarity. Changes of the channel formations can be modelled in appropriately scaled models only, where the density of the channel-bed material is varied with the strong compaction (loosening) of the model material. — Models that are distorted in respect to both the depth and the particle size and density of the sediment can only yield qualitative information on the processes taking place within certain ranges of the hydraulic regime, but one should be extremely cautious in estimating the numerical value of time variation of processes and of the water depth. Physical scale models must be tested for at least one characteristic flow and after identification it must be verified against another set of data measured in the prototype, using available records. The above statements imply, unfortunately, the need for using larger and more expensive scalemodels than before, which is not too encouraging for the practicing specialists of hydraulic design.