Modeliranje cevne turbine z diagonalnim gonilnikom z računalniško dinamiko tekočin

Rosec, Žiga (author), Hočevar, Marko (mentor), Petkovšek, Martin (comentor)

Da odgovorimo na potrebo po novi turbini nižjih specifičnih hitrosti, ki bo ohranjala prednosti Saxo turbin, smo izdelali novo enojno regulirano vertikalno cevno turbino, ki z diagonalnim gonilnikom omogoča nižjo specifično hitrost. Zaradi stroškov in časa potrebnega za izvajanje eksperimentalnega preizkušanja vodnih turbin, smo izvedli numerične simulacije za vrednotenje delovanja nove turbine. Na podlagi računalniške dinamike tekočin, so bile izvedene simulacije za različne obratovalne točke nove turbine. Pri izvajanju simulacij smo upoštevali predpostavke za nestisljiv enofazni tok. Predstavljene in razložene so uporabljene vodilne enačbe, z izbranim turbulentnim modelom SST. Iz simuliranih obratovalnih točk, je bil modeliran školjčni diagram, ki ima v primerjavi s Saxo turbino zaradi enojne regulacije manjše delovno območje optimalnega izkoristka. Nova konfiguracija doseže cilj nižjih specifičnih hitrosti, na področju med Francisovimi in diagonalnimi tipi turbin. S podrobnejšo analizo treh obratovalnih točk, smo predstavili kavitacijske, in tokovne razmere po turbini. Na področju delnih obremenitev, pride do pojava medlopatične vrtinčne kavitacije in opletajočega kavitacijskega vrtinca v sesalni cevi. Opazovani pojavi so primerljivi s tistimi v Francisovih turbinah.

• Language: Slovenian
• Keywords: vodne turbine, računalniška dinamika tekočin, Navier-Stokes enačbe, turbulentni model SST, školjčni diagram, specifična hitrost
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: FS - Faculty of Mechanical Engineering
• Place of publishing: Ljubljana
• Publisher: [Ž. Rosec]
• Year: 2019
• Number of pages: XXII, 72 str.
• PID: 20.500.12556/RUL-109635
• UDC: 621.224:532.5:004.942(043.2)
• COBISS.SI-ID: 16927259
• Publication date in RUL: 06.09.2019

ROSEC, Žiga, 2019, Modeliranje cevne turbine z diagonalnim gonilnikom z računalniško dinamiko tekočin [online]. Master’s thesis. Ljubljana : Ž. Rosec] . [Accessed 14 June 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=109635

Secondary language

• Language: English
• Title: Modelling of pipe turbine with a diagonal runner using computer fluid dynamics

Abstract

To answer the need for a new water turbine, with lower specific speeds, that would maintain all of the advantages of Saxo turbines. We designed a new single regulated vertical tubular turbine, with a diagonal runner, that enables lower specific speeds. Rather than performing expensive and time consuming experimental tests for water turbines, we used numerical simulations for evaluation of working parameters for the new turbine. Computational fluid dynamics were used to simulate different operating points. With the simulations, we have assumed incompressible single-phase flow. We presented and explained all the used leading equations, with the SST turbulence model. From the simulated operating points, we modelled the hill diagram for the new turbine, which has a smaller area of optimal performance compared to Saxo turbines. The new configuration acquires lower specific speeds between Francis and diagonal type turbines. With a more extensive analyzation, we observed three separate operating points and present cavitation and flow conditions in the turbine. In part load operation, we observed the emergence of inter-blade cavitating vortices and vortex rope in draft tube. The observed conditions are similar to those in Francis type turbines.

• Keywords: water turbines, computational fluid dynamics, Navier-Stokes equations, turbulent model SST, hill chart, specific speed