Combustion characteristics were compared for aerosols of nanocomposite powders with the composition 2B + Ti, blended boron and titanium powders with the same bulk composition, and aluminum, Nanocomposite powders were prepared by arrested reactive milling. Experiments were conducted in a constant-volume explosion vessel filled with N2/O2/CH4 mixtures, with volumetric oxygen concentration fixed at 22.5% and methane concentration varied from 0 to 12%. The flame temperature for aluminum powders remained close to 2560 K, whereas for the nanocomposite 2B + Ti, it increased from about 2180 to 2370 K as the methane concentration increased from 0 to 12%. Burn rates were consistently higher for the nanocomposite 2B + Ti powder, followed by aluminum and then by the blended 2B + Ti powder. The efficiency of combustion for all fuels was assessed by comparing the predicted and experimental portions of the combustion energy per unit mass of metal fuel used to produce the heated gaseous products. Nanocomposite 2B + Ti outperformed aluminum for all environments, with increasing difference in efficiency at higher methane concentrations. It was concluded that nanocomposite 2B + Ti powders enable one to achieve rapid and highly efficient combustion in both dry and wet gaseous environments.
All Science Journal Classification (ASJC) codes
- Aerospace Engineering
- Fuel Technology
- Mechanical Engineering
- Space and Planetary Science