Numerička simulacija procesa spreja i analiza utjecaja koeficijenata modela raspadanja goriva

undergraduate thesis

• Title (english): Numerical simulation of spray process and parametrisation of the atomisation model coefficients
• Author: Andrea Gadžić
• Mentor: Milan Vujanović (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2016-03-02, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering

Abstract

U ovome je radu pomoću računalne dinamike fluida izvršena validacija Euler-Eulerovog višefaznog modela stvaranja spreja vršenjem simulacija unutar programskog paketa FIRE®. Verifikacija modela utvrđivana je uspoređivanjem rezultata dobivenih simulacijama s postojećim eksperimentalnim podacima, preuzetim s web stranice Engine Combustion Network grupe.

Kroz rad se promatra valjanost matematičkog modela primijenjenog na proces visokotlačnog ubrizgavanja goriva u dizel motor. Na temelju ekoloških zahtjeva, zbog sve većeg zagađenja atmosfere, u industriji se obraća velika pozornost na smanjenje štetnih emisija i povećanje efikasnosti procesa izgaranja, što je usko povezano s procesima miješanja goriva i zraka te stvaranja spreja. Upravo se zbog toga veliki resursi ulažu u razvoj matematičkih modela pomoću kojih bi se dovoljno dobro opisali procesi visokotlačnog ubrizgavanja i stvaranja spreja. Prilikom visokotlačnog ubrizgavanja dolazi do raspadanja tekućeg goriva u sitne kapljice, što se naziva primarnim i sekundarnim raspadanjem, te njihovog naknadnog isparavanja. Kod računalnih simulacija ubrizgavanja goriva potrebno je voditi računa o pravilnom obliku spreja, dužini penetracije tekućeg i isparenog goriva te intenzitetu isparavanja. Višefazni sprej opisan je odabirom najboljeg seta koeficijenata već postojećih modela unutar programskog paketa FIRE® i rezultati simulacije uspoređeni su s eksperimentalnim podacima.

Abstract (english)

The focus of this work is on validation of the Euler-Eulerian multiphase spray modelling approach by using the AVL’s CFD software FIRE®. Verification of the model was performed by comparing the simulation results with the existing experimental data, downloaded from the Engine Combustion Network group’s website.

In this work, the multiphase spray module is used for simulating the high-pressure diesel fuel injection. Based on environmental demands, due to the increase in atmosphere pollution, there is great consideration on reduction of harmful emissions and on combustion process efficiency increasement. This is closely related to the fuel-air mixing and spray modelling processes. Because of that, a huge ammount of resources are invested in the development of mathematical models that could be used for better description of high pressure fuel injection and spray processes. During the high pressure injection the liquid core undergoes disintegration into smaller droplets which tend to disintegrate into even smaller ones. This processes are called primary and secondary break-up processes. Simultaneously, the droplets tend to evaporate. In the numerical simulations of fuel injection it is necessary to take care of the proper spray form, liquid and vaporized fuel penetration length and evaporation intensity during the computer simulation. Multiphase spray is defined by selecting the best set of coefficients of the existing models within the software package FIRE® and simulation results are compared with experimental data.

• Keywords: računalna dinamika fluida; Euler-Euler; visokotlačno ubrizgavanje; sprej
• Keywords (english): computational fluid dynamics; Euler-Eulerian; high-pressure injection; spray
• Language: croatian
• URN:NBN: urn:nbn:hr:235:877035
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka strojarstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-05-22 16:24:45