Comparison of detonation characteristics for typical binary blended fuel

Abstract For optimum utilization of explosive energy sources, it is significant to investigate detonation initiation and propagation characteristics of typical blended fuel containing aluminum particles with respectively JP-10, PO (propylene oxide) or EE (ethyl ether). A numerical model to examine the critical detonation initiation of dust/gas binary blended fuel was first proposed. The critical energy of detonation initiation of 50%Al:50%JP-10, 50%Al:50%PO and 50%Al:50%EE at overall concentrations of 280, 240, stoichiometric, 110, 80 and 50 g/m3 was numerically obtained. A compression wave was generated by the ignition source and expansion of combustion products. The interaction of flame with shock increases the surface area of the flame and creates strong vorticity, then local multiple explosions are established and amplified to direct initiation of detonation. Results reveal that the critical energy of detonation initiation reaches the lowest at stoichiometric concentration, and appears a typical ‘U’ shape behavior versus concentration. Specifically, the critical energy of detonation initiation is 500 J (0.1768 MJ/m2), 450 J (0.1592 MJ/m2) and 500 J (0.1768 MJ/m2) for respective stoichiometric concentration. 50%Al:50%EE has the lowest critical energy of detonation initiation at fuel-lean side, and 50%Al:50%JP-10 has the lowest at fuel-rich side, whereas 50%Al:50%PO has the lowest nearly at stoichiometry. In terms of detonation parameters, 50%Al:50%JP-10 achieves the highest overpressure at far fuel-lean side, and 50%Al:50%EE achieves the highest at far fuel-rich side, whereas 50%Al:50%PO achieves the highest nearly at stoichiometry. The onset process of stable detonation also reveals the detonation sensitivity of binary blended fuel.