Laser-Induced Ignition and Combustion Behavior of Individual Graphite Microparticles in a Micro-Combustor

Processes

Shengji Li¹  Minqi Zhang²  Shuhang Chang²  Yue Wang²  Xuefeng Huang² 

[1] College of Materials and Environmental Engineering, Hangzhou Dianzi University, Hangzhou 310018, China;Institute of Energy, Department of Physics, Hangzhou Dianzi University, Hangzhou 310018, China;

关键词: microscale combustion;    graphite;    photophoresis;    repetitive extinction;    laser ignition;   

DOI  :  10.3390/pr8111493

来源: DOAJ

【 摘 要 】

Microscale combustion has potential application in a micro power generator. This paper studied the ignition and combustion behavior of individual graphite microparticles in a micro-combustor to explore the utilization of carbon-based fuels at the microscale system. The individual graphite microparticles inside the micro-combustor were ignited by a highly focused laser in an air flow with natural convection at atmospheric temperature and pressure. The results show that the ignition of graphite microparticles was heterogeneous. The particle diameter had a small weak effect on ignition delay time and threshold ignition energy. The micro-combustor wall heat losses had significant effects on the ignition and combustion. During combustion, flame instability, photophoresis, repetitive extinction and reignition were identified. The flame structure was asymmetric, and the fluctuation of flame front and radiation intensity showed combustion instability. Photophoretic force pushed the graphite away from the focal point and resulted in extinction. Owing to large wall heat loss, the flame quickly extinguished. However, the graphite was inductively reignited by laser.

【 授权许可】

Unknown