Abstract
This research compared the performance of a cylindrical mesoscale combustor against two planar mesoscale combustors, which include the shape of the flame front, temperature of the combustor axis and the combustor wall, and the resulting flammability limit. The combustor used has a circular, square and rectangular cross-section. All three combustors have the same cross-section area and combustion chamber volume. The flame holder used is a double narrow slit. The fuel used is liquefied petroleum gas with a pure oxygen oxidizer. The experiment results showed that the cylindrical combustor produces a more even flame shape that fills the combustion chamber and there is no clear separation between the sides of the flame on each side of the narrow slit. A high ratio of the entrance to average velocity results in a large adverse pressure gradient which generates vortex and recirculation behind the flame holder which gives the mixture a longer chance in the combustion chamber (prolonged residence time). The flame front shape affects the temperature of the combustor axis. The flame front shape that fills the entire combustion chamber has a higher flame temperature than the separate flame front shape. The circular combustor has the highest average axis temperature, but it has the lowest combustor wall temperature. This fact shows that the circular combustor has the smallest heat loss from the flame to the combustor wall. Furthermore, a circular mesoscale combustor has the most extensive stability map. For the same volume, the circular combustor has a lower surface area to volume ratio, thus the heat loss is also low. The dead zone area also becomes narrower, only at a low reactant rate. Rectangular combustors have the largest surface area to volume ratio, thus the losses are also the biggest. Despite the narrowest flammability limits, rectangular combustors have the highest average wall temperatures
Highlights
In these two decades, there has been an extraordinary increase in the request for products in a portable form
This paper provides a better understanding of the effect of the entrance velocity to the average velocity ratio that determines the flame shape, flow pattern and vortex formation related to heat loss and flame stabilization, temperature distribution on the combustor wall
An experimental study of electro-spraying and ethanol combustion on a mesoscale conducted on a combustor with a catalyst showed ethanol combustion efficiency could be increased by 4.5 %, which proves that platinum catalysts can accelerate ethanol decomposition [12]
Summary
There has been an extraordinary increase in the request for products in a portable form. One of them is the energy source. There have been many studies on energy sources in portable form, among other fuel cells [1, 2], microbattery [3], etc. One of the important things in creating a portable energy source is power density. The highest energy density that we know is nuclear, [4], the one is hydrogen and hydrocarbon fuel. People prefer the combustion of hydrocarbon over nuclear for portable energy sources because the handling and safety are more secure. The high energy density of hydrocarbon fuels creates great opportunities for developing portable combustion-based power generation systems [5]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
