Free-flow discharge characteristics of an overshot gate: A non-hydrostatic numerical modeling approach
Pretočnost prostega preliva čez zaklopko: Pristop nehidrostatičnega numeričnega modeliranja
- Avtorji: Yebegaeshet T. Zerihun
- Citat: Acta hydrotechnica, vol. 35, no. 63, pp. 101-115, 2022. https://doi.org/10.15292/acta.hydro.2022.08
- Povzetek: Ravne zaklopne zapornice z vrtiščem na spodnjem robu se v veliki meri uporabljajo za merjenje pretoka v namakalnih sistemih z odprtimi kanali. Kljub svoji preprosti obliki ima prosti preliv čez tak objekt precejšnjo ukrivljenost tokovnic in strm naklon gladine, zaradi česar je predpostavka o porazdelitvi hidrostatičnega tlaka neveljavna. Zato je pristop plitvega toka (kot je npr. uporaba po globini povprečenih Navier-Stokesovih enačb) neustrezen za analizo pretočnih karakteristik zaklopke. Z uporabo Boussinesqovega modela povprečne globine so bili pogoji kritičnega toka, ki temeljijo na tem pristopu nižjega reda, razširjeni, kar je privedlo do enačbe za pretočni koeficient prostega preliva, ki implicitno vključuje dinamične učinke pretoka. Razviti model je bil testiran za primere prostega preliva, z zadovoljivim ujemanjem med računskimi rezultati in eksperimentalnimi podatki. Na splošno se je izkazalo, da je predlagani model sposoben natančno simulirati ostro ukrivljeni tok čez zaklopko. Študija je pokazala, da relativna globina preliva izrazito vpliva na značilnosti ukrivljenega transkritičnega toka in s tem na pretočni koeficient prostega preliva. Poleg tega ima kot naklona zmeren vpliv na pretočne karakteristike zaklopke polne širine pri naklonih manjših od 56°.
- Ključne besede: Zaklopka, pretočna krivulja, vrtilni jez, nehidrostatični tok, pretočni koeficient, merjenje pretoka.
- Polno besedilo: a35yz.pdf
- Viri:
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