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Algoritam za optimalnu raspodjelu površina sapnica difuzora podmorskog ispusta
Algorithm for Optimal Distribution of Diffuser Nozzle Areas of a Submarine Outfall

Vanja Travaš1, Davor Stipanić2

Sažetak/Abstract: 

U radu se predlaže iterativni numerički algoritam razvijen u svrhu određivanja optimalne raspodjele površina otvora sapnica duž difuzora podmorskog ispusta. Za zadanu geometriju toka, predloženi numerički postupak dovodi do raspodjele površina otvora sapnica potrebnih za osiguravanje jednolikog izlaznog protoka i nužnog početnog razrjeđenja u bliskom polju. Postupak omogućuje i identifikaciju površina otvora sapnica potrebnih za osiguravanjem nejednolikog rasporeda protoka koji je prethodno bio zadan. Nepoznate vrijednosti površina otvora i izlaznih brzina dobivaju se istodobno pomoću dvije međudjelujuće iterativne petlje. Za dane vrijednosti izlaznih brzina, u vanjskoj iterativnoj petlji, proračunavaju se površine sapnica i konstitutivne jednadžbe za gubitak tlaka. Dobivene vrijednosti se zatim koriste u unutarnjoj iterativnoj petlji, u kojoj se, pomoću Newton-Raphsonove metode, definira sljedeća aproksimativna vrijednost izlaznih brzina. Postupak se ponavlja sve dok oba konvergencijska kriterija nisu ispunjena. Osim teorijskog pregleda i pripadajućeg numeričkog algoritma, predstavljeno je i obrađeno nekoliko numeričkih primjera.

 

The paper proposes an iterative numerical algorithm developed for determining optimal distribution of nozzle opening areas along the diffuser of a submarine outfall. For the given flow geometry, the proposed nu­merical procedure results in a distribution of nozzle opening areas needed for ensuring a uniform outlet flow and the required initial dilution in the near field. The procedure also facilitates the determination of nozzle opening areas necessary for ensuring uneven distribution of the previously given flow. The unknown values of the nozzle opening areas and outlet velocities are obtained simultaneously by means of two interactive iterative loops. For the given values of the outlet velocities, nozzle areas and constitutive equations for pressure loss are calculated in the outer iterative loop. The obtained values are then used in the inner iterative loop where the next approximate value of the outlet velocities is determined by the Newton-Raphson method. The procedure is repeated until both convergence criteria are met. In addition to a theoretical overview and the associated numerical algorithm, several numerical examples are also presented.

Kategorija: 
Pregledni članak / Review Paper
Ključne riječi/Key words: 

difuzorska sekcija, optimizacijski algoritam, podmorski ispust, stacionarno strujanje

diffusor section, optimisation algorithm, submarine outfall, stationary flow

Podaci o autorima/Authors affiliations: 

1Građevinski fakultet Sveučilišta u Rijeci, Radmile Matejčić 3, 51000 Rijeka, vanja.travas@gradri.hr

 

2Teh projekt, d.o.o., Fiorello La Guardia 13/V, 51000 Rijeka

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