DNS of droplet evaporation and combustion in a swirling combustor
نویسندگان
چکیده
Turbulent multi-phase combustion is encountered in a number of engineering applications, such as internal combustion engines and gas-turbine aircraft engines. Therefore, the ability to perform accurate numerical simulations of these systems is of paramount importance to improve their design and efficiency. However, the underlying physics of spray combustion are extremely complicated. The liquid phase undergoes primary and secondary atomization. The resulting droplets are subject to evaporation, condensation, further breakup, or collision and coalescence with other droplets. The resulting vapor in the gas phase undergoes turbulent mixing, supplying the flame with unburned evaporated fuel. These concurrent processes of liquid-phase dynamics and evaporation, turbulence and combustion interact and strongly affect each other. Much pioneering effort has been dedicated to DNS of 2-D spray combustion in simple configurations and many interesting features have been obtained (Miller & Bellan 1999; Reveillon 2007). To gain a better understanding of the interactions between combustion and evaporation in a more realistic case, DNS of a 3-D swirling n-heptane spray flame is presented here. The structure characteristics of the spray flame are analyzed. Both premixed and diffusion flames are observed. The simulation is also used to extract data relevant to combustion modeling for future research.
منابع مشابه
Direct numerical simulation of three-dimensional swirling n-heptane spray flames
Spray combustion is encountered in many engineering applications, such as internal combustion engines and gas-turbine aircraft engines. In these systems, the concurrent processes of liquid atomization, droplet evaporation, turbulent dispersion, and combustion interact and strongly affect each other, which makes experimental measurement and high-fidelity simulation challenging. To understand the...
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