Vpliv prisotnosti NO2 v primarnem zraku na proces zgorevanja in nastanek izpustov onesnažil

magistrsko delo magistrskega študijskega programa II. stopnje Strojništvo

Neža Müller (Author), Tine Seljak (Mentor)

Abstract

Zaostrovanje okoljske zakonodaje na področju izpustov škodljivih snovi spodbuja razvoj naprednih konceptov zgorevanja, pri čemer se kot ena izmed glavnih strategij uporablja recirkulacija produktov zgorevanja. Poleg znižanja vsebnosti kisika v oksidantu in povečanja njegove specifične toplote se z recirkulacijo produktov zgorevanja v proces vnaša sledove aktivnih spojin, med katerimi je tudi NO2. Cilj magistrskega dela je eksperimentalno raziskati vpliv prisotnosti NO2 na zgorevanje zemeljskega plina. Meritve smo izvedli v batnem motorju s homogeno zmesjo pri vrtilni frekvenci 1500 min-1, navorih 25 Nm in 100 Nm ter razmernikih zraka 1,4; 1 ter 0,85. V vsaki delovni točki smo v proces dozirali štiri različne koncentracije NO2 v razponu od 30 ppm do preko 400 ppm. Na podlagi pridobljenih meritev sestave izpušnih plinov smo izvedli občutljivostno analizo zgorevalnega procesa na adicijo NO2 in analizirali kinetične vplive NO2. Izkaže se, da NO2 v pogojih nižjih temperatur lahko deluje kot promotor vžiga na račun hitrejše tvorbe OH radikalov, kar vodi do pospeševanja hitrosti oksidacijskih reakcij in s tem hitrejšega doseganja ravnotežnega stanja, hkrati pa vpliva tudi na spremembo v sestavi izpušnih plinov.

Keywords

magistrske naloge;zgorevanje;adicija NO2;reakcijski mehanizem;občutljivostna analiza;izpusti onasnežil;recirkulacija izpušnih plinov;hitrostna konstanta;

Data

Language:	Slovenian
Year of publishing:	2025
Typology:	2.09 - Master's Thesis
Organization:	UL FS - Faculty of Mechanical Engineering
Publisher:	[N. Müller]
UDC:	621.43.019.6:661.984:519.6(043.2)
COBISS:	241106691
Views:	102
Downloads:	29
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	Effect of NO2 in primary air on combustion and emission formation process
Secondary abstract:	The increasing stringency of environmental legislation is encouraging the development of combustion concepts with minimal impact on environment and very low emissions. One of the main strategies to achieve this is the recirculation of combustion products. In addition to reduction of oxygen content within the oxidant and increase in specific heat capacity of the mixture, the recirculation of combustion products introduces also trace amounts of active compounds into the process, including NO2. The aim of this thesis is to experimentally investigate the influence of NO2 presence on the combustion of natural gas. The measurements were carried out in a spark-ignition engine with a homogeneous mixture at engine speed of 1500 min-1, torque of 25 Nm and 100 Nm and normalized air-fuel ratios of 1,4; 1 and 0,85. In each operating point, primary combustion air was doped with four different concentrations of NO2, ranging from 30 ppm to over 400 ppm. Based on the exhaust gas composition measurements, a sensitivity analysis of the combustion process to NO2 addition was performed and the kinetic effects of NO2 were analysed. It turns out that NO2 can act as an ignition promoter under lower temperature conditions due to the faster formation of OH radicals, leading to an acceleration of oxidation reaction rates and thus a faster attainment of the equilibrium state, while also affecting the composition of the exhaust gases.
Secondary keywords:	master thesis;combustion;NO2 doping;reaction mechanism;sensitivity analysis;emissions of pollutants;exhaust gas recirculation;reaction rate constant;
Type (COBISS):	Master's thesis/paper
Study programme:	0
Thesis comment:	Univ. Ljubljana, Fak. za strojništvo
Pages:	XXII, 74 str.
ID:	26712182