Močno vezane računalniške simulacije s tokom gnane Darrieusove turbine

doktorska disertacija

Matjaž Fleisinger (Author), Matej Vesenjak (Mentor), Matjaž Hriberšek (Co-mentor)

Abstract

Za pridobivanje energije iz vodotokov se v zadnjem času uporabljajo tudi turbine, ki so postavljene prosto v tok in predstavljajo bistveno manjši poseg v prostor kot običajne elektrarne. Postopki za preračun zmogljivosti tovrstnih turbin temeljijo na različnih aerodinamičnih modelih, medtem ko so se metode računalniške dinamike tekočin na tem področju pričele uporabljati šele pred kratkim. Tudi slednje se izvajajo z vnaprej predpisanimi parametri, ki predstavljajo predvideno ustaljeno obratovanje turbine. Za določanje obratovalne karakteristike je tako potrebno več simulacij pri različnih obratovalnih parametrih. Za poglobljeno razumevanje delovanja teh turbin so bili razviti novi pristopi računalniških simulacij, ki zajemajo pristop s tokom gnane turbine, kar predstavlja bistveno bolj realne pogoje v simulaciji. S tem pristopom je mogoče z eno simulacijo napovedati celotno obratovalno karakteristiko za določeno hitrost toka. S takšnim pristopom so bile izvedene parametrične simulacije geometrijskih parametrov turbine. Lopatice tovrstnih turbin, posebej pri namestitvi z vodoravno osjo vrtenja, predstavljajo dolge in vitke strukture, ki so med obratovanjem izpostavljene vodnemu toku. Ta vpliva na njihovo deformacijo, slednja pa na obtekanje lopatice. Posledica tega so spremembe v zmogljivostih turbine. Z uporabo kombinacije pristopa s tokom gnane turbine in močno vezanih simulacij medsebojnega vpliva tekočine in strukture je mogoče ovrednotiti vpliv deformacije lopatic na zmogljivosti turbine. Zato je bila razvita programska rutina, ki omogoča hkratno uporabo pristopa s tokom gnane turbine in močno vezanih simulacij. Za validacijo na novo razvitih postopkov simulacije je bil izveden eksperiment s pomanjšanim modelom turbine na naravnem vodotoku, pri katerem so bili izmerjeni povesi lopatice med obratovanjem turbine. Rezultati eksperimenta in simulacij so pokazali dobro ujemanje. Primerjava rezultatov simulacij izvedenih z uveljavljenimi postopki in na novo razvitimi pristopi je pokazala na znatne razlike v delovanju turbine, zato je smiseln nadaljnji razvoj in uporaba na novo razvitih pristopov.

Keywords

vodne turbine;vodna energija;močno vezane simulacije;računalniška dinamika tekočin;metoda končnih elementov;Hidrokinetične turbine;Disertacije;Darrieusove turbine;Delovanje;

Data

Language:	Slovenian
Year of publishing:	2014
Typology:	2.08 - Doctoral Dissertation
Organization:	UM FS - Faculty of Mechanical Engineering
Publisher:	M. Fleisinger]
UDC:	[004.94:532.5]:621.224(043.3)
COBISS:	17800214
Views:	1799
Downloads:	152
Average score:	0 (0 votes)
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Other data

Secondary language:	English
Secondary title:	FULLY COUPLED COMPUTER SIMULATIONS OF A FLOW DRIVEN DARRIEUS TURBINE
Secondary abstract:	Among conventional systems for river energy extraction the new types of turbines are considered in the recent time that can be deployed in a free stream without impounding of a waterway and represent a minor impact on an environment when compared to conventional power stations. Procedures for analysis of these turbines are based on different aerodynamic models, while modern methods based on computational fluid dynamics have been applied only recently. Even those are performed using prescribed operational parameters, such as constant rotational velocity. To acquire the whole operational characteristics more simulations have to be performed. For a deeper understanding of operating principles the new simulation procedure has been developed, which employ flow driven approach, which enables more realistic condition in a simulation. Using such approach it is possible to acquire the whole operational characteristics of a turbine for a certain flow velocity within a single simulation. The blades of such turbines, especially in horizontal axis position, represent long and slender structures that are exposed to hydrodynamic loading during operation. This causes blade deformation, which instantly changes flow conditions around it. The consequence is altered performance of a turbine. Using a combination of flow driven approach and fully coupled fluid structure interaction in a simulation it is possible to assess the influence of blade deformation to the turbine performance. Therefore the routine has been developed to enable simultaneous use of fluid structure interaction and a flow driven approach. To validate the newly developed simulation procedures the experiment with a scaled model of a turbine was performed on a natural waterway. The results of experiment and simulation showed a good agreement. Comparison of simulations based on conventional and newly developed approaches pointed considerable differences in turbine operation. Therefore it is reasonable to use developed simulation procedure as well as its further development.
Secondary keywords:	Darrieus turbine;hydrokinetic turbines;fully coupled simulations;computational fluid dynamics;finite element method;
URN:	URN:SI:UM:
Type (COBISS):	Dissertation
Thesis comment:	Univ. v Mariboru, Fak. za strojništvo
Pages:	VIII, 161 str.
ID:	8728549