https://ogma.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:15335 Wed 11 Apr 2018 09:49:35 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:30969 −3) on the deflagration of methane in a hybrid form. The work addressed the characteristic of hybrid flame deflagration behaviour including the flame velocity, pressure profile, dynamic and static pressure. Two concentrations of coal dust were introduced to the methane deflagrations, which were 10 g m⁻³ and 30 g m⁻³. The results revealed that the presence of a diluted coal dust of 10 g m⁻³ significantly enhanced the flame travelling distance of a 5% methane concentration, from 12.5 m to 20.5 m. Introducing a 30 g m⁻³ coal dust concentration also enhanced the flame travelling distance of a 5% methane concentration, from 12.5 m to the EDT (End of Detonation Tube, 28.5 m). This enhancement was associated with boosting the flame velocity and the over pressure rise. For a higher methane concentration (i.e., a 7.5% methane concentration), the flame of the methane reached the EDT. Introducing 10 g m⁻³ coal dust to a 7.5% methane explosion increased the flame intensity signal, from 1 V to the maximum reading value (10.2 V), and enhanced the flame velocity at the EDT by about 14 m s⁻¹ and finally, increased the stagnation pressure at the end of the detonation tube from 1.25 bar to 4.6 bar.]]> Wed 04 Sep 2019 10:06:45 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:32400 -1 for the range of methane mixtures exploded. The severity of the explosions increased with increasing igniter energy. The maximum pressure rise rate increased from 83 bar.s ^-1 for 1 kJ igniter to 90 bar.s^-1 for 2 kJ igniter, to 155 bar.s^-1 for 5 kJ igniter and to 222 bar.s^-1 for 10 kJ igniter. The severity of the explosions increased with increased coal dust concentration. At 2.5% methane-air mixture, the pressure rise rate increased from 4 bar.s^-1 to 114 bar.s^-1 when the coal dust concentration increased from 50 g.m^-3 to 100 g.m^-3, respectively.]]> Thu 31 May 2018 09:05:09 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:55948 Thu 18 Jul 2024 20:25:10 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:7360 Sat 24 Mar 2018 08:40:15 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:30647 50), and moisture content, impact on the MAIT. For coal dust concentrations less than 1000 g.m⁻³, the MAIT decreases with increasing coal dust concentrations. On the other hand, for low concentrations of 100 to 15 g.m⁻³, the MAIT becomes more reliable for particle size D₅₀ rather than for volatile matters.]]> Sat 24 Mar 2018 07:33:22 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:29996 st) and explosive region of hybrid fuel mixtures present in Ventilation Air Methane (VAM) were investigated. Experiments were carried out according to the ASTM E1226-12 guideline utilising a 20 L spherical shape apparatus specifically designed for this purpose. Results: obtained from this study have shown that the presence of methane significantly affects explosion characteristics of coal dust clouds. Dilute concentrations of methane, 0.75-1.25%, resulted in coal dust clouds OPR increasing from 0.3 bar to 2.2 bar and boosting the K_st value from 10 bar m s^-1 to 25 bar m s^-1. The explosion characteristics were also affected by the ignitors' energy; for instance, for a coal dust cloud concentration of 50 g m^-3 the OPR recorded was 0.09 bar when a 1 kJ chemical ignitor was used, while, 0.75 bar (OPR) was recorded when a 10 kJ chemical ignitor was used.For the first time, new explosion regions were identified for diluted methane-coal dust cloud mixtures when using 1, 5 and 10 kJ ignitors. Finally, the Le-Chatelier mixing rule was modified to predict the lower explosion limit of methane-coal dust cloud hybrid mixtures considering the energy of the ignitors.]]> Sat 24 Mar 2018 07:28:52 AEDT ]]>