TY - CONF A1 - Mishra, Kirti Bhushan T1 - Lessons learned from recent fuel storage fires T2 - 11th International Conference on Combustion and Energy Utilization (ICCEU) CY - Coimbra, Portugal DA - 2012-05-09 PY - 2012 AN - OPUS4-25847 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishra, Kirti Bhushan T1 - CFD Prediction of spill characteristics of liquid organic peroxides T2 - IGUS EOS Meeting CY - Berlin, Germany DA - 2012-05-07 PY - 2012 AN - OPUS4-25850 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter T1 - CFD simulation to predict the performance of a peroxy-fuel burner N2 - new burner concept for peroxy-fuels is proposed. The performance of the proposed peroxy-fuel burner is predicted with the help of Computational Fluid Dynamics (CFD) simulation. It is found that peroxy-fuel burner not only requires considerable less amount of fuel for the same output/power but also at the same time the overall size of the processing unit can be reduced. As peroxy-fuels contain oxygen atoms within the molecule itself a similar to oxy-fuel combustion environment is created without even supplying pure oxygen. CFD simulations also support the above facts and demonstrate the existence of less favorable conditions to form NOx. T2 - 38th National conference on fluid mechanics and fluid power CY - Bhopal, India DA - 15.12.2011 KW - Burner KW - Peroxy-fuels KW - Performance KW - CFD simulation PY - 2011 IS - Paper HT-07 SP - 1 EP - 6 AN - OPUS4-25380 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishra, Kirti Bhushan T1 - CFD analysis of peroxy-fuel combustion T2 - 34th International Symposium on Combustion CY - Warsaw, Poland DA - 2012-07-29 PY - 2012 AN - OPUS4-26368 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishra, Kirti Bhushan T1 - CFD simulation to predict the performance of a peroxy-fuel burner T2 - 38th National Conference on Fluid Mechanics and Fluid Power CY - Bhopal, India DA - 2011-12-15 PY - 2011 AN - OPUS4-25414 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishra, Kirti Bhushan T1 - Applications of peroxy-fuels in vehicle propulsion T2 - COMBURA Symposium 2012 CY - Maastricht, Netherlands DA - 2012-10-03 PY - 2012 AN - OPUS4-26615 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schälike, Stefan A1 - Chun, Hyunjoo A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter A1 - Schönbucher, A. T1 - Mass burning rates of di-tert-butyl peroxide pool fires - experimental study and modeling N2 - Data and predictions for the mass burning rates of di-tert-butyl peroxide (DTBP) pool fires (0.003 m < pool diameter < 3 m) are presented. The mass burning rates of DTBP fires are up to five times higher and are less dependent on pool diameter compared to hydrocarbon pool fires caused by an additional heat release rate due to exothermic decomposition reaction in the liquid phase. This heat release rate is calculated using a first-order reaction kinetic obtained from microcalorimetric measurements. A new model is derived considering the heat release rate due to the decomposition reaction, which is shown to be 40% of the heat release rate radiated to the pool surface. With the presented model, which also includes physical quantities, especially the limiting fuel concentration for upward flame propagation, it is possible to predict the mass burning rates of large DTBP pool fires. The predicted values are in very good agreement with the experiments. KW - Di-tert-butyl peroxide (DTBP) KW - Exothermic decomposition reaction KW - Mass burning rate KW - Pool fire PY - 2013 DO - https://doi.org/10.1080/00102202.2012.726664 SN - 0010-2202 SN - 1563-521X VL - 185 IS - 3 SP - 408 EP - 419 PB - Gordon and Breach CY - New York, NY AN - OPUS4-27902 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishra, Kirti Bhushan T1 - Peroxy-fuels: potential applications in combustion engines T2 - 11th International Congress on Engine Combustion Processes - Current Problems and Modern Techniques CY - Ludwigsburg, Germany DA - 2013-03-14 PY - 2013 AN - OPUS4-27874 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schälike, Stefan A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter A1 - Schönbucher, A. T1 - Validated CFD simulation to predict the flame temperatures and species mass fractions of a multiple n-heptane pool fire N2 - The flame temperatures T of a multiple n-heptane pool fire d = 6 cm, N = 5, D/d = 0.33 are measured with type S thermocouples and predicted with Large Eddy Simulation (LES) and an assumed pdf-approach containing a detailed kinetic with 112 species and 800 elementary reactions. Multiple pool fires show higher flame temperatures up to ≈ 200 K in comparison to single pool fires. CFD simulation is in good agreement with the experimental results and a validation is performed. It can be shown that multiple fires have an enhanced air-entrainment leading to an increased formation of OH radicals and consequently to the observed higher flame temperatures. T2 - ECM 2013 - 6th European combustion meeting CY - Lund, Sweden DA - 25.06.2013 KW - Validated CFD simulation KW - Flame temperatures KW - Species mass fractions KW - Multiple n-heptane pool fire PY - 2013 SN - 978-91-637-2151-9 IS - Paper P5-46 SP - 1 EP - 6 AN - OPUS4-28861 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter T1 - "Deviceless" self-sustained oscillatory diffusive burning of TBPB and hybrid fuels N2 - An extraordinary deviceless self-sustained oscillatory diffusive burning is observed in tert-butyl peroxybenzoate (TBPB) (technical pure) and hybrid fuel, i.e., TBPB and kerosene (both 50%) flames when burned in form of pool fires. Such oscillations or more precisely self-sustained deviceless control of mass burning (flow) is not reported till date. Generally, devices comprising electronic control system and/or mechanical means (valves) are necessary to produce such oscillatory burning or control of fuel flow. This unique oscillation is strongly recorded for pool diameters of 6 cm ≤ d ≤ 11 cm beyond which the effect was weakened and unseen (hid) visually. The fuel regression (loss) takes place in irregular time steps and is formulated in form of a step function. The variation in fuel mass burning rates, visible flame lengths and radiation heat fluxes with time are measured as respective representatives of oscillations. The periodicity in the strongest oscillations in relative visible flame lengths is investigated and the measured data are found to be best fitted in sinusoidal form. Both, chemical and thermal effects are shown to be possibly responsible for such effects. Furthermore, a theory is offered to characterise similar effect showing fuels. KW - Self-sustained KW - Oscillatory burning KW - TBPB KW - Kerosene KW - Diffusion flame KW - Flow rate control PY - 2013 DO - https://doi.org/10.1016/j.fuproc.2013.07.010 SN - 0016-2361 SN - 0378-3820 SN - 1873-7153 VL - 116 SP - 339 EP - 345 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-29013 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter ED - Leipertz, A. T1 - Peroxy-fuels: potential applications in combustion engines N2 - Present work deals with the potential usage of peroxy-fuels (usually known as organic peroxides) in engine combustion processes. Although as additives (in small quantities < 5% to conventional fuels e.g. diesel, gasoline) peroxy-fuels are well known for many years their commercial applications as a main or primary fuel are not investigated in detail as such except a few. Since they are thermally unstable and energetic their safety demands great care during processing which restricts their commercial exploitation. However, once the issues with safety are resolved they can be much more advantageously employed than conventional fuels. Some of these advantages are: significant amount of fuel saving, reduction in amount of inducted air or even in the complete absence of air i.e. anaerobically, smaller volume of combustion (chamber), oxygenated fuel quality and low emissions. In this study we introduce an idea to develop the components of an engine operating solely on peroxy-fuels. The engine concept is based on single and multiple injectors in a cylinder with special material coating to ensure a temperature controlled processing. T2 - 11th International congress on engine combustion processes - current problems and modern techniques CY - Ludwigsburg, Germany DA - 14.03.2013 KW - Industrial fires KW - Storage units KW - Safety measures KW - Explosion KW - Overpressure KW - CFD simulation PY - 2013 SN - 3-931901-87-4 N1 - Serientitel: Berichte zur Energie- und Verfahrenstechnik (BEV) – Series title: Berichte zur Energie- und Verfahrenstechnik (BEV) IS - 13.1 SP - 157 EP - 164 AN - OPUS4-27951 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schälike, Stefan A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter A1 - Schönbucher, A. T1 - Experimentelle Untersuchung der Massenabbrandraten multipler n-Heptan und Di-tert-butylperoxid Poolfeuer N2 - Es werden Experimente zur Bestimmung der Massenabbrandraten von multiplen Poolfeuern präsentiert. Als Modellsubstanzen dienen n-Heptan und Di-tert-butylperoxid (DTBP). Es werden Versuche im Labormaßstab mit Durchmessern von d = 6 cm und relativen Abständen von 0.08 ≤ D/d ≤ 4 beschrieben und durch Feldversuche mit Pooldurchmessern d = 1.5 m und relativen Abständen zwischen den Pool von 0.17 ≤ D/d ≤ 1 ergänzt. Es kann gezeigt werden, dass die Massenabbrandraten multipler Feuer im Vergleich zu Einzelfeuern mit gleicher Brennstoffoberfläche bis zu einem Faktor 5.9 (n-Heptan) und 1.6 (DTBP) erhöht sind. Die Erhöhung ist abhängig vom relativen Abstand zwischen den Pools D, der Anzahl der Pools N und vom jeweiligen Brennstoff und zeigt ein lokales Maximum, welches mit dem Merging-Bereich der Flammenverschmelzung zusammenfällt. Die Massenabbrandrate als Funktion des relativen Abstandes zwischen den Pools kann durch eine Vergrößerung der Flammenbodenoberfläche infolge Flammenverschmelzung erklärt werden. T2 - 3. Magdeburger Brand- und Explosionsschutztag / vfdb-Workshop CY - Magdeburg, Germany DA - 22.03.2013 KW - Multiple Poolfeuer KW - Massenabbrandraten KW - n-Heptan KW - DTBP PY - 2013 SN - 978-3-00-041601-9 SP - 1 EP - 11 AN - OPUS4-27982 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishra, Kirti Bhushan T1 - Dispersion characteristics of flammable liquids: A CFD study T2 - 4th International Congress on Computational Mechanics and Simulation (ICCMS 2012) CY - Hyderabad, India DA - 2012-12-09 PY - 2012 AN - OPUS4-27368 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishra, Kirti Bhushan T1 - CFD simulation of hybrid fuel combustion T2 - Thirty Ninth National Conference on Fluid Mechanics and Fluid Power (NCFMFP) CY - Surat, India DA - 2012-12-13 PY - 2012 AN - OPUS4-27529 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter A1 - Krebs, Holger T1 - Lessons learned from recent fuel storage fires N2 - Industrial fire and explosion hazards due to accidents in fuel storage units have gained a considerable attention in recent years. Both, the regulatory bodies and scientific communities are heavily concerned about the proper safety measures to avoid such calamities in the future. This paper aims to bring some essentials related to the hazards that arose from recent fuel storage fire accidents occurring in Buncefield, UK (2005), Puerto Rico, USA (2009) and Sitapura, India (2009). The potential similarities behind occurrence of these accidents are studied. The applicability of various methods (models) and also computer simulations to estimate the safety distances according to the international standards for both explosion and fire hazard are verified. The overpressures caused by the Vapor Cloud Explosions (VCE) and radiation fluxes emitted by the fires are considered for respective explosion and fire hazard estimations. The prime focus is placed on the regulations laid down by the National Fire Protection Agency of the United States and the European Norms. KW - Industrial fires KW - Storage units KW - Safety measures KW - Explosion KW - Overpressure KW - CFD simulation PY - 2013 DO - https://doi.org/10.1016/j.fuproc.2012.08.003 SN - 0016-2361 SN - 0378-3820 SN - 1873-7153 VL - 107 SP - 166 EP - 172 PB - Elsevier CY - Amsterdam AN - OPUS4-27598 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schälike, Stefan A1 - Mishra, Kirti Bhushan A1 - Malow, Marcus A1 - Berger, Anka A1 - Wehrstedt, Klaus-Dieter A1 - Schönbucher, A. ED - Pierucci, S. ED - Klemes, J.J. ED - De Rademaeker, E. ED - Fabiano, B. ED - Buratti, S.S. T1 - Mass burning rate of a large TBPB pool fire - experimental study and modeling N2 - Data and prediction for the mass burning rate of a tert-butyl-peroxy-benzoat (TBPB) pool fire (pool diameter = 3 m) is presented. The mass burning rates of TBPB fires are up to six times higher and less dependent on pool diameter compared to hydrocarbon pool fires caused by an additional heat release rate due to exothermic decomposition reaction in the liquid phase. This heat release rate is calculated using a 1st order reaction kinetic obtained from micro calorimetric measurements. A new model is derived considering the heat release rate due to the decomposition reaction which is shown to be 100 % of the heat release rate radiated to the pool surface. With the presented model, including also physical quantities, especially the limiting fuel concentration for upward flame propagation, it is possible to predict the mass burning rates of large TBPB pool fires. The predicted values are in very good agreement with the experiments. T2 - 14th International symposium on loss prevention and safety promotion in the process industries CY - Florence, Italy DA - 12.05.2013 KW - Mass burning rate KW - TBPB (tert-butyl-peroxy benzoat) KW - Pool fire KW - Experimental study KW - Modeling PY - 2013 SN - 978-88-95608-22-8 DO - https://doi.org/10.3303/CET1331143 SN - 1974-9791 N1 - Serientitel: Chemical engineering transactions – Series title: Chemical engineering transactions IS - 31 SP - 853 EP - 858 PB - AIDIC, Associazione Italiana di Ingegneria Chimica CY - Milano AN - OPUS4-28501 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schälike, Stefan A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter A1 - Schönbucher, A. T1 - Limiting distances for flame merging of multiple n-heptane and di-tert-butyl peroxide pool fires N2 - Experiments to determine the limiting distances for flame merging of multiple pool fires are presented. As model substances n-heptane and di-tert-butyl peroxide are used. Laboratory scale tests with a Diameter d = 6 cm and relative distances between the pools of 0.08 ≤ D/d ≤ 4 are described and complemented with field experiments with a diameter d = 1.5 m and relative distances between the pools of 0.17 ≤ D/d ≤ 1. Three regions for flame merging are observed and limiting distances are determined. A merging Region with the limiting distance Dmerg/d within which all flames merge together over the complete burning time. A transition region with the limiting distance Dtran/d within which some flames merge together while other flames are separated from each other. A separated region within which all flames are completely separated from each other. A correlation against the number of burning pools is presented to predict the limiting distances Dmerg/d und Dtran/d. T2 - ICheaP-11 - 11th International conference on chemical & process engineering CY - Milan, Italy DA - 02.06.2013 KW - Multiple fires KW - Flame merging KW - Mass burning rate KW - Limiting distances KW - Pool fire KW - Experimental study KW - Di-tert-butyl peroxide PY - 2013 SN - 978-88-95608-23-5 DO - https://doi.org/10.3303/CET1332021 SN - 1974-9791 N1 - Serientitel: Chemical engineering transactions – Series title: Chemical engineering transactions IS - 32 SP - 121 EP - 126 PB - AIDIC, Associazione Italiana di Ingegneria Chimica CY - Milan AN - OPUS4-28646 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter T1 - Diffusive burning characteristics of peroxy-fuels N2 - The diffusive burning characteristics of four peroxy-fuels (usually known as liquid organic peroxides) and one hydrocarbon fuel are experimentally investigated targeting alternative fuels (or as additives to conventional fuels) for the future. Measurements are performed in form of pool fires with pool diameters in the range between 1 cm and 1 m. Mass, momentum and energy transfer studies are carried out by measuring the mass burning rate, flame length, flame temperature and radiation heat transfer across the liquid fuel and gaseous flame. It has been shown that comparatively much less mass of peroxy-fuels and pressure drop (required to maintained the flow) of fuel are required to produce a given heat flux. The momentum delivered by the peroxy-fuel vapours are order of magnitude higher than for hydrocarbons making the visibility of flame to be 4–5 times larger. A heat balance analysis shows that the total heat release rate of a peroxy-fuel fire is contributed equally by convection and radiation. Finally, the three E's (Efficiency, Economy and Emission) are discussed in the context of present experimental results followed by some recommendations concerning safe handling of the proposed fuels. KW - Burning characteristics KW - Peroxy-fuels KW - Hydrocarbons KW - Pool fires KW - Three E’s PY - 2013 DO - https://doi.org/10.1016/j.fuel.2013.05.031 SN - 0016-2361 VL - 113 SP - 158 EP - 164 PB - Elsevier CY - Amsterdam AN - OPUS4-28711 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Vela-Wallenschus, Iris A1 - Schälike, Stefan A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter A1 - Schönbucher, A. T1 - Kritische thermische Abstände bei wechselwirkenden KW- und Peroxid-Poolfeuern N2 - In verfahrenstechnischen Anlagen kann es während des Umgangs, des Transports und der Lagerung durch Freisetzung und anschliesender Zündung von brennbaren Flüssigkeiten zu Lachen-, Pool- oder Tankfeuern kommen. Die sich ausbildenden Feuer konnen große Schäden an benachbarten verfahrenstechnischen Anlagen und Personen verursachen. Im Unterschied zu Einzelfeuern sind multiple Pool- und Tankfeuer aufgrund ihrer Wechselwirkungseffekte sicherheitstechnisch von besonderer Bedeutung. Mit Di-tert-butyl-peroxid (DTBP) und n-Heptan als Leitsubstanzen werden Labor- und Feldexperimente (d ≤ 1.5 m) mit wechselwirkenden Poolflammen (N ≤ 9) in einer Matrixanordnung bei relativen horizontalen Abständen D/d zwischen den Pools im Bereich 0.16 ≤ D/d ≤ 4 durchgeführt. Die Phänomene der Flammenverschmelzung (Flammenfusion) in Abhängigkeit vom Poolabstand D/d werden experimentell untersucht und modelliert. T2 - 11. Fachtagung Anlagen-, Arbeits- und Umweltsicherheit CY - Köthen, Germany DA - 07.11.2013 KW - Wechselwirkende Poolfeuer KW - KW-Poolfeuer KW - Peroxid-Poolfeuer KW - Sicherheitsabstände KW - Spezifische Ausstrahlung KW - Bestrahlungsstärke PY - 2013 SN - 978-3-86011-058-4 N1 - Geburtsname von Vela-Wallenschus, Iris: Vela, I. - Birth name of Vela-Wallenschus, Iris: Vela, I. IS - P-06 SP - 1 EP - 17 AN - OPUS4-29549 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schälike, Stefan A1 - Mishra, Kirti Bhushan A1 - Ziemann, Sylvia A1 - Wehrstedt, Klaus-Dieter A1 - Schönbucher, A. ED - Beyer, M. ED - Stolz, T. T1 - Massenabbrandraten organischer Peroxide unter besonderer Berücksichtigung der thermischen Stabilität N2 - Die Flüssigkeitstemperatur Temperatur in der flüssigen Phase unmittelbar im Grenzbereich zur Gasphase während eines Abbrandes organischer Peroxide überschreitet die Onset-Temperatur der beginnenden exothermen Zersetzungsreaktion des Peroxids, so dass diese zu berücksichtigen ist. Für die Peroxide Di-tert-butyl-Peroxid (DTBP) und tert-butyl-peroxybenzoat (TBPB) muss daher bei der Berechnung des Wärmerückstromes ein zusätzlicher Term für die Zersetzung in der Flüssigkeit additiv ergänzt werden. Der Umsatz der Zersetzungsreaktion wird unter den Bedingungen eines CSTR modelliert und erfolgt auf Basis einer Reaktionskinetik 1. Ordnung. Es kann gezeigt werden, dass der Wärmestrom in einem DTBP-Poolfeuer ≈ 40 % und einem TBPB-Poolfeuer ≈ 100 % des Wärmerückstromes durch Wärmestrahlung entspricht. Durch Q-Punkt-d können die vergleichsweise hohen Massenabbrandraten und die relative Unabhängigkeit der Massenabbrandraten vom Pooldurchmesser erklärt werden. Über eine Energiebilanz wird ein Modell basierend auf physikalischen Parametern entwickelt, das die Massenabbrandraten großer Poolfeuer, in sehr guter Übereinstimmung mit den experimentellen Ergebnissen, vorhersagt. T2 - 13. BAM-PTB-Kolloquium zur chemischen und physikalischen Sicherheitstechnik CY - Braunschweig, Germany DA - 18.06.2013 KW - Poolfeuer KW - Massenabbrandrate KW - Organische Peroxide KW - Thermische Stabilität KW - Onset-Temperatur PY - 2013 SN - 978-3-95606-062-5 DO - https://doi.org/10.7795/210.20130801E SN - 1868-5838 SP - 40 EP - 47 AN - OPUS4-29815 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter A1 - Krebs, Holger T1 - Amuay refinery disaster: The aftermaths and challenges ahead N2 - Amuay refinery disaster (2012) is another recent example of Vapor Cloud Explosion (VCE) and fire accidents preceded by Buncefield (2005), Puerto-Rico (2009) and Jaipur (2009), respectively [9]. The incident has left many safety issues behind which must be repeatedly addressed. Unfortunately, the lessons taught by previous similar events are just not understood carefully. It reveals that the proper safety measures for such facilities were either underestimated or were not accounted seriously. Consequently, the resulting overpressures from explosion and the subsequent thermal radiation from tank fires have once again proved to be disastrous to both mankind and infrastructure. This article highlights the aftermaths of Amuay incident and addresses the challenges put forward by it. Furthermore, a comparative study is performed between such incidents to analyze the similarities and how they could have been avoided. KW - Refinery disaster KW - Vapor cloud explosion KW - Fire KW - Safety distance KW - Overpressure KW - Radiation PY - 2014 DO - https://doi.org/10.1016/j.fuproc.2013.10.025 SN - 0016-2361 SN - 0378-3820 SN - 1873-7153 VL - 119 SP - 198 EP - 203 PB - Elsevier CY - Amsterdam AN - OPUS4-29816 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Mishra, Kirti Bhushan T1 - Experimental investigation and CFD simulation of organic peroxide pool fires (TBPB and TBPEH) N2 - Time averaged mass burning rate (m˙′′f ), flame length (H), temperature (T ), irradi- ance (E) and surface emissive power (SEP ) of TBPB (tert -butyl peroxybenzoate) and TBPEH (tert-butyl peroxy-2-ethylhexanoate) pool fires are measured for six pool di- ameters (d = 0.059 m, 0.107 m, 0.18 m, 0.5 m, 1 m and 3.4 m) at BAM in house and outside test facility. The measured heats of combustion (–Δhc) of TBPB and TBPEH are 30113 kJ/kg and 34455 kJ/kg and the specific heat capacities at constant pressure (cp) are 1.8 kJ/(kg K) and 2.1 kJ/(kg K) respectively. The measured m˙′′f of TBPB and TBPEH pool fires are in the range of 0.37 kg/(m2 s)≤ m˙ ′′ f ≤ 0.83 kg/(m2 s) and show little dependence on the pool diameter d, and are four to sixty times higher (for d = 1 m) than that of hydrocarbon pool fires. It is shown that the mass burning rates of the investigated organic peroxides can be represented as an exponential function of the self-accelerating decomposition temperature (SADT). Low SADT implies that the organic peroxide pool fires burn at a much higher m˙′′f than hydrocarbon pool fires. Fuel Froude numbers (Frf) of TBPB and TBPEH are 5 to 100 times (depending on d) higher than for hydrocarbon pool fires. Due to higher Frf the H of TBPB and TBPEH (measured with a S-VHS Videocamera) are found to be two times larger (d = 1 m) than corresponding pool fires of hydrocarbons. Heskestads flame length correlation predicts the Hd (d = 3.4 m) of TBPB and TBPEH pool fires much better than Thomas and Fay correlations. The measured time averaged flame temperatures T (d = 3.4 m) for TBPB and TBPEH pool fires are in the range of 1400 K ≤ T ≤ 1500 K and are 200 K to 300 K higher than for JP-4, kerosene and gasoline. The irradiances of the TBPB and TBPEH pool fires measured by radiometers are E (Δy/d = 0.3) = 45 kW/m2 and E = 98 kW/m2 which are two to ten times higher in comparison to the corresponding n-pentane, super gasoline and diesel pool fires. So the thermal safety distances for organic peroxide pool fires are larger by a factor four in comparison to the hydrocarbon pool fires. An infrared thermography system is used for the determination of SEP of TBPB and TBPEH pool fires. The values of surface emissive power for TBPB and TBPEH are SEP (d = 3.4 m) = 196 kW/m2 and SEP = 258 kW/m2 and thus the SEP are by a factor of approximately two higher than for hydrocarbon pool fires. A self-sustained pulsating Hd (’W’-Effect) is found in TBPB pool flames and is further analysed to explain the reason of occurance on the basis of chemical structure of the fuel and discontinuous heat flux back from flame to the liquid pool. CFD simulations of TBPB and TBPEH pool fires at d = 0.18 m, 0.5 m, 1 m, 3.4 m and 8 m are carried out using the Unsteady Reynolds Averaged Navier Stokes (URANS) equa- tions. The three-dimensional geometries have been discritized with unstructured hybrid grids, with the number of cells in the range of 1 million. Depending on the grid resolu- tion and the pool diameter time steps of 0.0001 s ≤ Δt ≤ 0.01 s for the CFD simulations are used. For solving the discritized equations a finite volume based implicit solver AN- SYS CFX has been used. For modelling the combustion, stoichiometric combustion for both peroxides are assumed. The temperature dependence of the reaction rate has been determined by the Arrhenius approach. For modelling the combustion eddy dissipation concept (EDC) model has been used. For turbulence buoyancy modified k- � and SAS (Scale Adaptive Simulation) turbulence models are used. For the thermal radiation and soot mass fraction discrete transfer radiation model and Magnusson soot model have been used. A new method is suggested for the prediction of mass burning rate (m˙′′f ) by CFD simula- tion. Both peroxide pool fires show approximately constant mass burning rate indepen- dent of d whereas m˙′′f of TBPEH are under predicted at the beginning but show relatively good agreement with measurements for large pool diameters (d = 1 m). In case of TBPB the CFD simulation over predicts the mass burning rate m˙′′f of small TBPB pool fires and shows a continuous decrease with d. CFD predicts the flame length H close to the measured data provided that the constants in Thomas equation are modified. The CFD predicted time averaged surface emission flame temperatures of TBPB and TBPEH pool fires (d = 3.4 m, 1437 K and 1542 K) are in good agreement with the measured time averaged flame temperatures. The CFD predicted SEP for TBPB and TBPEH pool fires (d = 3.4 m, 217 kW/m2 and 288 kW/m2) are also in agreement with the measured values. From the CFD predicted irradiance ECFD it is possible to determine the thermal safety distances from large pool fires of hydrocarbons and organic peroxides. T3 - BAM Dissertationsreihe - 63 KW - Pool fires KW - organic peroxides flame characteristics KW - safety distance KW - CFD simulation PY - 2010 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-950 SN - 978-3-9813550-6-2 SN - 1613-4249 VL - 63 SP - 1 EP - 150 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-95 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter A1 - Krebs, Holger T1 - Boiling liquid expanding vapour explosion (BLEVE) of peroxy-fuels: Experiments and computational fluid dynamics (CFD) simulation N2 - Fire and explosion hazards associated with storage and transportation of flammable materials have been a matter of great interest in the recent times. BLEVE is a scenario that occurs when a closed fuel container is subjected to heat for a longer duration. Such events are disastrous to human beings and assets both. In the past there have been numerous studies on BLEVEs and fireballs of hydrocarbon fuels, e.g. kerosene, gasoline, LPG, LNG and others. Though, the fireballs of peroxy-fuels are not looked into detail as such. This article tries to overcome this lack of knowledge. Both, experimental investigation and CFD simulations are performed to measure and predict the fireball characteristics of a peroxy-fuel. Due to thermal decomposition in the liquid phase and active oxygen content a peroxy-fuel fireball burns at a very fast rate and emit higher thermal radiation whereas exhibits smaller diameter and elevation compared to hydrocarbons. That eventually leads to consideration of larger safety distances from them which are also verified by CFD results. KW - BLEVE KW - Hydrocarbons KW - Peroxy-fuels KW - Safety distances KW - CFD simulation PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-334184 DO - https://doi.org/10.1016/j.egypro.2015.02.082 SN - 1876-6102 VL - 66 SP - 149 EP - 152 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-33418 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter T1 - Decomposition effects on the mass burning rate of organic peroxide pool fires N2 - The mass burning rate of pool fires of organic peroxides do not vary appreciably with the pool size as have been observed for the hydrocarbons. Instead the decomposition temperature largely controls the same. The dependence of mass burning rate on the decomposition temperatures namely self-accelerating decomposition temperature (SADT) and extrapolated onset temperature measured by differential scanning calorimetry (DSC) for organic peroxide pool fires are identified and correlations are developed. KW - Decomposition KW - SADT KW - Pool fire KW - Mass burning rate KW - Organic peroxides KW - DSC PY - 2012 DO - https://doi.org/10.1016/j.jlp.2011.06.014 SN - 0950-4230 SN - 1873-3352 VL - 25 IS - 1 SP - 224 EP - 226 PB - Butterworth CY - Guildford, Surrey AN - OPUS4-25020 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter T1 - CFD simulation of hybrid fuel combustion N2 - CFD (Computational Fluid Dynamics) simulation results of hybrid fuel combustion i.e. one hydrocarbon and one peroxy-fuel in an industrial burner are reported. The addition of one of the most stable peroxy-fuels (Di-tert-butyl peroxide, DTBP) in one reference hydrocarbon fuel i.e .in methane is studied. Both fuels are assumed to be in the gas phase and are mixed in form of a multi component mixture. The content of peroxy-fuel in methane is varied between 5 % to 50 %. CFD results indicate that the addition of DTBP (> 10 %) drastically enhance the reaction rates of methane and hence ensure an efficient combustion. It is also found that 50 % of DTBP addition doubles the reaction rate which helpsto burn the entire fuel in a relatively smaller volume of the chamber and leads to an economical processing of the material. The influences of the same on NOx production are also discussed. T2 - NCFMFP 2012 - 39th National conference on fluid mechanics and fluid power CY - Surat, Gujarat, India DA - 13.12.2012 KW - CFD KW - Hybrid fuel KW - Hydrocarbon KW - Peroxy-fuel KW - Combustion PY - 2012 SN - 978-81-925-494-0-8 DO - https://doi.org/10.13140/2.1.2528.3205 IS - FMFP2012 - 209 SP - 1 EP - 7 AN - OPUS4-27587 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter A1 - Krebs, Holger T1 - Lessons learned from recent fuel storage fires N2 - Industrial fire and explosion hazards due to accidents in fuel storage units have gained a considerable attention in the recent times. Both the regulatory bodies and scientific communities are heavily concerned about the proper safety measures to avoid such calamities in future. This paper aims to bring some essentials related to the hazards arose from the recent fuel storage fire accident occurred in Buncefield, UK (2005), Puerto Rico, USA (2009) and Sitapura, India (2009). The potential similarities behind occurrence of these accidents are studied. The applicability of various methods (models) and also computer simulations to estimate the safety distancesaccording to the international standards for both explosion and fire hazard are verified. Theoverpressures caused by the Vapor Cloud Explosion (VCE) and radiation flux emitted by the fireare considered for respective explosion and fire hazard estimations. The prime focus is placedon the regulations laid down by the National Fire Protection Agency of the United States and the European Norms. T2 - ICCEU 2012 - 11th International conference on combustion and energy utilization CY - Coimbra, Portugal DA - 09.05.2012 KW - Industrial fires KW - Storage units KW - Safety measures KW - Explosion KW - Overpressure KW - CFD simulation PY - 2012 SP - 1 EP - 10 AN - OPUS4-26186 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter T1 - CFD modeling of spill characteristics of flammable liquids N2 - Present work deals with safe storage and transportation of flammable liquids. A flammable liquid can spill as a result of an overflow, leakage, failure of mechanical parts, mistakes by personnel or some deliberate acts. If the spilled fuel finds an ignition source depending on flammability limits a pool fire develops. The fire and spill continue until steady state conditions are achieved. Under such conditions a steady state diameter of spill (pool) can be established. However, this theoretical diameter is based on the assumption that the volumetric spill and burning rates are equal. Determination of spill size (D) independent of burning rate (or if there is no burning) is not reported as such in the existing literature. We develop a Computational Fluid Dynamics (CFD) model to predict the spill size which is independent of burning rate and is based on the definition of overflow Reynolds number (Re). By changing Re different spill scenarios can be predicted. Here five cases with Re = 100, 500, 1000, 2000 and 2500 are considered. One liquid hydrocarbon (Jet A) and one organic peroxide (DTBP: di-tert butyl peroxide) spill are simulated. The model considers two phases i.e. air as a continuous phase and liquid fuel as a dispersed phase. Fig. 1 shows such predicted spill sizes for DTBP for five overflow Reynolds numbers. The spill characteristics of Jet A and DTBP found to be similar for a defined Reynolds number. A correlation between spill size and overflow Reynolds number is also established. In order to estimate the spill diameter and the height of vapor cloud the explosion limits of air-fuel mixtures are taken into consideration. The model makes it possible to estimate the spill characteristics of a wide variety of flammable liquids. T2 - 22nd Journées d´Etudes of the Belgian section of the combustion institute CY - Heverlee, Belgium DA - 11.09.2012 KW - Flammable liquids KW - Spill characteristics KW - CFD modeling KW - Overflow Reynolds number KW - Jet A KW - DTBP KW - Vapor cloud PY - 2012 SP - 18 EP - 19 AN - OPUS4-27924 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter T1 - Applications of peroxy-fuels in vehicle propulsion N2 - The combustion of petroleum derived conventional fuels (diesel, gasoline etc.) takes place relatively at a slower rate. In many applications they are forced to combust faster in order to match the specific power/output requirement. To accelerate the combustion process fuel (and oxidiser) supply has to be correspondingly increased by some means. These imply the necessity of high pressure fuel feed pump, air compressor (super or turbo charger) and a large volume of chamber to combust these mixtures. As an outcome the overall compactness of the vehicle declines. Furthermore, as an additional consequence in form of emissions e.g. COx and NOx occur as a result of fast combustion of fuel and air, We investigate combustion of a dass of energetic materials commonly known as organic peroxides (or peroxy-fuels) as a main fuel in vehicle propulsion. Peroxy-fuels are typically known as reaction enhancer’s, polymerizing agents and cross linkers. Sometimes, they have been also utilised in small amounts (1% to 5%) to conventional fuels successfully. It was found that combustion process was improved and emission was drastically turned down. Therefore, they are termed as combustion improvers as well. Also it was shown that with a peroxy-fuel an engine can be run anaerobically. T2 - COMBURA 2012 - Combustion research and application CY - Maastricht, The Netherlands DA - 03.10.2012 KW - Peroxy-fuels KW - Vehicle propulsion KW - Pool flame KW - Internal combustion engine PY - 2012 SP - 49 EP - 50 AN - OPUS4-26821 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -