A Mathematical Investigation of Premixed Lycopodium Dust Flame in a Small Furnace

In the present study, a comprehensive mathematical method is developed to realize the flame expansion in the melting furnace zones. For this purpose, the furnace is composed of two zones: flame and post flame zones. Two different scenarios are covered in this research: Using lycopodium as a substitute fuel which is then converted to methane after the vaporization process, supplying the system with methane directly as a conventional fuel. The equations governing the problem with the required boundary conditions are developed and solved in each zone. The obtained results show great compatibility with the experimental findings in this research. Since lycopodium as the replacement fuel mostly contains volatile materials, one of the challenges in this study lies on understanding the effect of particle vaporization on the temperature distribution in a furnace. It is concluded that the average temperature in zones α1, α2, β1, and β2, is reduced by about 5 K, while it is increased by approximately the same amount in zones χ1, χ2, δ1, and δ2 after considering lycopodium as a fuel. Moreover, the role of vaporization and radiation on the combustion characteristics is studied in details. The achieved results from this analysis can be implemented in several industrial applications aiming for improving the energy efficiency outcome from their systems.

Effect of Stabilized Water-Diesel Emulsions on External Combustion Characteristics

This study presents an experimental investigation of emulsified fuels with water content of 10%, 20% and 30% by volume, using a small furnace under steady combustion conditions. Pure diesel is used as a baseline in the conducted external combustion for comparison purposes. The study found that water content in the emulsion has strong impact on the flame temperature, the flame heat release and the combustion efficiency. The 20% water-diesel emulsion showed a lower flame temperature and higher combustion efficiency. Using the proper water-diesel emulsion, 20%, the heat release rate of the emulsified fuels is comparable to the one obtained in the pure diesel case. The highest flame temperature and heat flux transfer to water jacket is achieved at pure diesel (0% water content). The optimum water content in diesel emulsion strongly depends on the liquid fuel nozzle design.

Inversion of 4f-states in CeB6 thermally excited at 430 K

The 4f states of Ce in a typical Kondo crystal, CeB6, are split into an excited state Γ7 and the ground state Γ8, with an excitation energy at 560 K. The electron-density distribution of the thermally excited state was measured at 430 K using a four-circle diffractometer equipped with a small furnace. In contrast to the previous results at lower temperature, electrons are transferred from B6 to Ce at 430 K. X-ray atomic-orbital analysis revealed that the 5d-Γ8 orbitals (the energy level of which is similar to that of the B-2p orbitals) are fully occupied and the 4f-Γ7 orbitals are more populated than the 4f-Γ8 orbitals. Fully occupied 5d-Γ8 makes the 4f-Γ8 states unstable and the energy levels of 4f-Γ7 and 4f-Γ8 are inverted.

Excavations of Two Iron Processing Sites at Scabgill and Boghall, Clydesdale, 1991

Summary Excavations were carried out on two sites containing traces of iron ore processing, as part of the N-W Ethylene Pipeline Project, funded by Shell Chemicals UK Ltd. The excavations at Scabgill revealed a small part of an iron ore processing site apparently dating to the later medieval period or earlier. At nearby Boghall, a small furnace was excavated, which, while not itself datable, was also used in the processing of low grade, bog iron ores.