Mathematical Modeling of Nanoparticle Cloud Combustion Incorporates the Effects of Particle Phase Change within the Reaction Zone of a Non-Premixed Combustion System Operating in a Counterflow Configuration

In this study, the multi-stage edge combustion of a particle cloud was modeled, and the effect of changing the fuel type on the change in the triple flame propagation velocity was considered. Due to the complexity of the instability issue, extensive studies on the instability in cloud particle combustion, especially the inherent instabilities in non-premixed combustion and the conditions and factors for the onset of oscillations, have not been conducted, and this phenomenon is not well understood. Therefore, in this study, by presenting a new mathematical model that includes the combustion of an iron cloud particle in a non-premixed system with a counterflow configuration, the effect of important phenomena such as non-adiabatic combustion has been investigated by considering thermal radiation and oscillatory instability. In this study, by presenting a comprehensive mathematical model that includes the melting process of nanoparticles during chemical reaction, the temperature profile and mass fraction in different combustion regions have been analyzed. The results show that increasing the Lewis number of the oxidant from ۱ to ۱.۷۵ causes a ۳۶.۴۲۸% increase in the maximum force from -۱.۱۲E-۸ N to -۱.۵۲۸E-۸ N. Reducing the Lewis number of the fuel from ۱ to ۰.۲۵ causes a slightly more than twofold increase in this force from -۱.۱۲E-۸ N to -۲.۲۵۸E-۸ N. Increasing the diameter of the nanoparticle increases the magnitude of the thermophoretic force. A ۶۶.۶۷% increase in the diameter of the nanoparticle, i.e., an increase from a diameter of ۱۵ to ۲۵ nm, causes a more than ۵-fold increase in the maximum force from -۴.۲۱۱E-۹ to -۲.۲۲۴E-۸. As the Lewis number of the fuel increases from ۰.۴ to ۲.۵, the flame temperature gradually decreases from ۰.۶۲۲۴ at the Lewis number ۰.۴ to ۰.۴۰۵۸ at the Lewis number ۲.۵.

کلیدواژه ها:

Nanoparticle cloud ، Phase change ، non-premixed combustion ، Counterflow ، Mathematical modeling