TY - CONF A1 - Mishra, K. B. A1 - Wehrstedt, Klaus-Dieter A1 - Krebs, Holger T1 - Prediction of overpressure in buried gas pipeline explosions T2 - 5. Magdeburger Brand- und Explosionsschutztage N2 - The explosion and fire incidents with buried gas pipelines are increasing globally e.g. San Bruno (USA, 2010), East Godavari (India, 2014) and Ludwigshafen (Germany, 2014) are only a few to quote. There are a number of parameters involved behind the occurrence of these incidents such as human mistake, intended efforts leading to major or minor leak, explosion due to depressurization, crater formation, spill of gaseous fuel in the nearby regions and pool/jet/crater fires. In continuation to [3] these parameters are investigated for Ludwigshafen incident in the present work. The semi-empirical and advanced CFD (Computational Fluid Dynamics) based models are utilized to assess the damages caused by the explosion overpressures. Recommendations are also provided on minimum safety distance to be considered for such pipelines to avoid/foresee/mitigate similar hazards in future. T2 - 5. Brand- und Explosionsschutztage 2017 CY - Magdeburg, Germany DA - 23.03.2017 KW - Buried gas pipeline KW - Explosion KW - Overpressure KW - CFD-Model KW - Safety distance PY - 2017 SN - 978-3-00-056201-3 DO - https://doi.org/10.978.300/0562013 SP - 1 EP - 8 AN - OPUS4-40193 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Blankenhagel, Paul A1 - Wehrstedt, Klaus-Dieter A1 - Xu, S. A1 - Mishra, K. B. A1 - Steinbach, J. T1 - A new model for organic peroxide fireballs JF - Journal of Loss Prevention in the Process Industries N2 - Organic peroxides are capable to form fireballs with explosive violence. Only fireball models for liquid hydrocarbon fuels are available for the assessment of the thermal radiation properties. Because the development of such fireballs usually differ from those of organic peroxides the properties need to be characterized by modified equations. In this study liquid organic peroxide fireballs from 16 kg to 155 kg substance masses are characterized and compared to selected existing correlations. Flame characteristics and irradiances are measured with infrared cameras and heat flux sensors. All fireballs are consequences of simulated worst case scenarios where filled steel drums are engulfed by fire with varying heat impact. The differences of the given semi-empirical equations and the presented experimental work are explained. A new model is proposed for organic peroxide fireballs by modifying the constants of the known equations. The thermal radiation impact and safety distances are calculated and compared. KW - Organic peroxide KW - Fireball KW - Thermal radiation KW - Safety distances PY - 2017 DO - https://doi.org/10.1016/j.jlp.2017.10.002 SN - 0950-4230 VL - 50 IS - Part A SP - 237 EP - 242 PB - Elsevier Science AN - OPUS4-43069 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Blankenhagel, Paul A1 - Wehrstedt, Klaus-Dieter A1 - Mishra, K. B. A1 - Steinbach, J. T1 - Prediction of organic peroxide fireball characteristics using CFD simulation T2 - Proceedings of the 8th European Combustion Meeting 2017 N2 - Single and multiple fireballs of di-tert-butyl peroxide are numerically investigated using ANSYS CFX. Calculations contain varying inlet conditions, scale-adaptive shear stress turbulence modeling and one-step combustion reaction on a three-dimensional hexahedral mesh. Time-resolved flame temperatures, sizes and thermal radiation are compared to experimental results. There, fireballs were generated by fire engulfment of steel drums containing 200 l substance. After a vigorous burning, the remaining peroxide forms single and multiple fireballs involving 10 % to 20 % of the initial amount. The comparison of all simulations and two selected experiments show the special numerical treatment required for organic peroxides. Finally, the numerical predictions of irradiance in 30 m distance to the fire show a good agreement for both experiments. This proves the use of CFD as an appropriate method for thermal hazard assessment and the prediction of safety distances for organic peroxide fireballs. T2 - 8th European Combustion Meeting 2017 CY - Dubrovnik, Croatia DA - 18.04.2017 KW - Organic peroxide KW - DTBP KW - Fireball KW - Steel drum KW - Simulation PY - 2017 SN - 978-953-59504-1-7 AN - OPUS4-39992 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Blankenhagel, Paul A1 - Wehrstedt, Klaus-Dieter A1 - Mishra, K. B. A1 - Steinbach, J. T1 - Fireballs as a possible hazard scenario of organic peroxides in steel drums T2 - MBE Tagungsband 2017 N2 - To simulate a full fire engulfment during transportation or storage a closed removable head steel drum filled with 200 l Di-tert-butyl peroxide (DTBP) is subjected to a wood fire. Due to the enormous heat flux and the exothermic self-decomposition large flames arise and finally multiple fireballs occur. The fireballs consume up to 20 % of the total mass (20 % equals to 31 kg). They are characterized by high surface emissive power and large flames associated with high thermal radiation causing spontaneous ignition of objects in the surrounding. The measured sizes of the DTBP fireballs are smaller compared to the results of the general equations for hydrocarbon fireballs. Because these equations are recommended by the Health and Safety Executive (UK) to be applicable for organic peroxides explicit comparisons of DTBP with LPG, diesel and gasoline concerning the characteristics of fireballs are carried out. Also the burning time is compared and confirms a faster combustion of the peroxide. Moreover, the development of size and emissive power for DTBP and diesel fireballs are compared in a normalized graph. The results provide the assumption that new empirical models are required to be developed for hazard assessment of organic peroxide fireballs. T2 - 5. Brand- und Explosionsschutztage 2017 CY - Magdeburg, Germany DA - 23.03.2017 KW - Organic peroxide KW - DTBP KW - Fireball KW - Steel drum KW - Simulation PY - 2017 SN - 978-3-00-056201-3 DO - https://doi.org/10.978.300/0562013 VL - 2017 SP - 1 EP - 9 PB - Otto-von-Guericke-Universität CY - Magdeburg AN - OPUS4-39994 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -