Dynamical Systems and Nonlinear Control Theory
Loire, Sophie, Fonoberov, Vladimir and Mezic, Igor (2009), "Combustion of methane in microchannels", ASME Conference Proceedings.
The interest in micropower generation using the high energy density provided by hydrocarbon fuels as a portable power and heat source has stimulated research on combustion in microdevices. As the length scale of a combustion channel is decreased, the surface area-to-volume ratio increases approximately inversely with the critical dimension. As a result, the influence of interfacial phenomena is amplified. The resulting high surface heat loss is a limiting factor to the size of microcombustor but using arrays of micro-combustors some of the surface heat loss in one channel is becoming heat source for its neighbors. Combustion of methane/air mixture can be described using simple heat and mass transport equations where the reaction rate of combustion depends on premixed gas concentration and gas temperature. In our model gas temperature depends on heat from reaction and heat gain or loss through the channel walls and channel wall temperature depends on energy released during combustion and/or external heating. The array of micro-combustors is modeled as combustion in thermally coupled channels. Using this model, combustion in an array of channels is studied as a function of gas velocity and distance between channels and is compared to the case of a single channel. Arrays of channels are shown to have self-sustained combustion when no such combustion is possible in a single channel.