Sewage sludge combustion model with reduced chemical kinetics mechanisms

Anton Žnidarčič (Avtor), Tomaž Katrašnik (Avtor), I. G. Zsély (Avtor), T. Nagy (Avtor), Tine Seljak (Avtor)

Povzetek

Commonly applied 3D CFD models lack suitable combustion description of fuels with complex composition, such as encountered in wastewater sludge specific applications. This significantly influences their prediction capability, in particular when used in small, confined combustion volumes. To tackle this challenge, it is necessary to introduce detailed chemical kinetic models for specifically tailored fuel surrogates, which ensure physically accurate description of local thermodynamic conditions and heat release rates. However, necessity to increase the level of detail of models needs to be balanced by their computational expenses to preserve their applicability when solving real engineering problems. With an aim to fill this gap, the present study significantly extends the existing surrogate model methods for applications in small-scale systems to include also reduced combustion kinetic mechanisms. The innovative extension applies Simulation Error Minimization Connectivity Method and involves tailoring of kinetic mechanisms to variable thermodynamic conditions and variable surrogate compositions, specific to sewage sludge combustion. Suitability of the proposed approach is confirmed with the 3-D CFD simulations maintaining similar level of accuracy within the design space of reduced mechanisms as well as in off-design conditions, while maintaining sufficient flexibility to adapt to different types and compositions of the sludge. Thereby, reduction of the in-model applied detailed ethanol and propene mechanisms from 47 and 71 species down to 33 and 34 species, respectively, was demonstrated together with linearly dependent decrease in computational time. The proposed model extension and resulting surrogate combustion model thus for the first time offer an efficient tool for affordable and accurate virtual design of small-scale combustion systems using fuels with complex chemical composition.

Ključne besede

combustion;chemical kinetics;sewage sludge;numerical simulations;reduced reaction mechanisms;

Podatki

Jezik:	Angleški jezik
Leto izida:	2021
Tipologija:	1.01 - Izvirni znanstveni članek
Organizacija:	UL FS - Fakulteta za strojništvo
UDK:	004.942:628.3(045)
COBISS:	58189827
ISSN:	0196-8904
Št. ogledov:	45
Št. prenosov:	18
Ocena:	0 (0 glasov)
Metapodatki:

Ostali podatki

Sekundarni jezik:	Slovenski jezik
Sekundarne ključne besede:	zgorevanje;kemijska kinetika;odpadni mulj;numerične simulacije;reducirani reakcijski mehanizmi;
Vrsta dela (COBISS):	Članek v reviji
Strani:	str. 1-15
Zvezek:	ǂVol. ǂ236
Čas izdaje:	May 2021
DOI:	10.1016/j.enconman.2021.114073
ID:	16146519