On droplet combustion of biodiesel fuel mixed with diesel/alkanes in microgravity condition
- Department of Mechanical Engineering, National Taiwan University, Taipei 10617 (China)
The burning characteristics of a biodiesel droplet mixed with diesel or alkanes such as dodecane and hexadecane were experimentally studied in a reduced-gravity environment so as to create a spherically symmetrical flame without the influence of natural convection due to buoyancy. Small droplets on the order of 500 {mu}m in diameter were initially injected via a piezoelectric technique onto the cross point intersected by two thin carbon fibers; these were prepared inside a combustion chamber that was housed in a drag shield, which was freely dropped onto a foam cushion. It was found that, for single component droplets, the tendency to form a rigid soot shell was relatively small for biodiesel fuel as compared to that exhibited by the other tested fuels. The soot created drifted away readily, showing a puffing phenomenon; this could be related to the distinct molecular structure of biodiesel leading to unique soot layers that were more vulnerable to oxidative reactivity as compared to the soot generated by diesel or alkanes. The addition of biodiesel to these more traditional fuels also presented better performance with respect to annihilating the soot shell, particularly for diesel. The burning rate generally follows that of multi-component fuels, by some means in terms of a lever rule, whereas the mixture of biodiesel and dodecane exhibits a somewhat nonlinear relation with the added fraction of dodecane. This might be related to the formation of a soot shell. (author)
- OSTI ID:
- 21227396
- Journal Information:
- Combustion and Flame, Vol. 156, Issue 10; Other Information: Elsevier Ltd. All rights reserved; ISSN 0010-2180
- Country of Publication:
- United States
- Language:
- English
Similar Records
Synthesis, droplet combustion, and sooting characteristics of biodiesel produced from waste vegetable oils
Preliminary investigation of soot formation from multicomponent droplet combustion