TY - JOUR A1 - Poli, Marco A1 - Imhof, H. A1 - Holst, N. A1 - Steinbach, J. T1 - Venting of Foaming Three-Phase Systems N2 - Designing pressure relief devices for three-phase systems consisting of solids, liquids and vapors requires an in-depth knowledge of the fluid dynamics and of the thermodynamic effects in the reactor. The behavior of foaming three-phase systems is, to date, still not well understood. In this research, these systems are systematically studied, taking the solid properties into account. Also, the applicability of two-phase pressure relief models to three-phase systems is investigated with the help of the simulation tool SAFIRE/Vent. The results obtained contribute significantly to the better design of pressure relief devices and to more accurate predictions of the three-phase venting behavior and the solid discharge. KW - Safety technology KW - Foam KW - Three-phase system KW - Safire/Vent KW - Level swell KW - Mass discharge KW - Pressure relief profile PY - 2009 DO - https://doi.org/10.1002/ceat.200800505 SN - 0930-7516 SN - 1521-4125 VL - 32 IS - 2 SP - 312 EP - 318 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-18746 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Blanchard, Robert A1 - Poli, Marco A1 - Grätz, Rainer ED - Suter, G. ED - de Rademaeker, E. T1 - Effect of ignition position on the run-up distance to DDT for hydrogen-air explosions T2 - 13th International symposium on loss prevention and safety promotion in the process industries CY - Brugge, Belgium DA - 2010-06-06 KW - Deflagration to detonation transition (DDT) KW - Ignition position KW - Hydrogen PY - 2010 SN - 978-90-76019-291 VL - 02 SP - 157 EP - 164 CY - Brugge, Belgium AN - OPUS4-21443 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Poli, Marco A1 - Blanchard, Robert A1 - Grätz, Rainer ED - Suter, G. ED - de Rademaeker, E. T1 - Venting of turbulent gas explosions T2 - 13th International symposium on loss prevention and safety promotion in the process industries CY - Brugge, Belgium DA - 2010-06-06 KW - Explosionsdruckentlastung KW - Simulation KW - ANSYS CFX KW - Explosionsschutz KW - Sicherheitstechnik PY - 2010 SN - 978-90-76019-291 VL - 02 SP - 165 EP - 172 CY - Brugge, Belgium AN - OPUS4-21442 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Poli, Marco A1 - Grätz, Rainer A1 - Schröder, Volkmar T1 - Limited applicability of gas explosion venting due to turbulence generation N2 - For the design of gas explosion venting systems for confinements only little guidance is given when considering the constructional boundary conditions or process conditions. For this reason conservative assumptions are prevalent in practice and in many cases the protective Systems become significantly oversized. Such safety margins in venting areas can lead to a critical acceleration of the pressure rise. Finally, a gas explosion at turbulent conditions caused by oversizing of the venting area rather leads to an under-sized system and supports the deflagration to detonation transition (DDT). The present investigation was focused especially on the influence of certain obstacles as well as the effect of the initial pressures on the explosion venting behavior of methane-air-mixtures and of hydrogen-air-mixtures. T2 - 2011 AIChE Spring meeting & 7th global congress on process safety CY - Chicago, IL, USA DA - 12.03.2011 KW - Gas explosion venting KW - Turbulent combustion KW - KG-value PY - 2011 IS - Topical 1 / #13 / 13h SP - 1 EP - 13 CY - New York, NY, USA AN - OPUS4-23376 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Blanchard, Robert A1 - Arndt, Detlef A1 - Grätz, Rainer A1 - Poli, Marco A1 - Scheider, Swen T1 - Explosions in closed pipes containing baffles and 90 degree bends N2 - There is a general lack of information on the effects of full-bore obstacles on combustion in the literature, these obstacles are prevalent in many applications and knowledge of their effects on phenomena including burning rate, flame acceleration and DDT is important for the correct placing of explosion safety devices such as flame arresters and venting devices. In this work methane, propane, ethylene and hydrogen-air explosions were investigated in an 18 m long DN150 closed pipe with a 90 degree bend and various baffle obstacles placed at a short distance from the ignition source. After carrying out multiple experiments with the same configuration it was found that a relatively large variance existed in the measured flame speeds and overpressures, this was attributed to a stochastic element in how flames evolved and also how they caused and interacted with turbulence to produce flame acceleration. This led to several experiments being carried out for one configuration in order to obtain a meaningful average. It was shown that a 90 degree bend in a long tube had the ability to enhance flame speeds and overpressures, and shorten the run-up distance to DDT to a varying degree for a number of gases. In terms of the qualitative effects on these parameters they were comparable to baffle type obstacles with a blockage ratios of between 10 and 20%. KW - Baffle KW - Bend KW - Deflagration to detonation transition KW - Explosion enhancement PY - 2010 DO - https://doi.org/10.1016/j.jlp.2009.09.004 SN - 0950-4230 SN - 1873-3352 VL - 23 SP - 253 EP - 259 PB - Butterworth CY - Guildford, Surrey AN - OPUS4-20843 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Poli, Marco A1 - Grätz, Rainer A1 - Schröder, Volkmar T1 - Influence of obstacles and initial pressure on turbulent gas explosion venting T2 - 19th International congress of chemical and process engineering (CHISA 2010) / 7th European congress of chemical engineering (ECCE-7) CY - Prague, Czech Republic DA - 2010-08-28 KW - Explosionsdruckentlastung KW - Turbulente Verbrennung KW - Explosionsschutz PY - 2010 SN - 978-80-02-02210-7 IS - F2.5 / 0911 SP - 1 EP - 7 CY - Prague, Czech Republic AN - OPUS4-21922 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Poli, Marco A1 - Grätz, Rainer A1 - Schröder, Volkmar ED - Pierucci, S. ED - Klemes, J.J. ED - De Rademaeker, E. ED - Fabiano, B. ED - Buratti, S.S. T1 - Limitations of gas explosion venting due to accelerated flame propagation and elevated initial pressure N2 - Many industrial processes include a gas explosion hazard. If safety measures are not adequate to prevent a potentially explosive atmosphere or to avoid effective ignition sources in enclosures, at least the effects of an explosion can be limited e.g. by gas explosion venting systems. For the design of gas explosion venting systems for confinements only little guidance is given when considering the constructional boundary conditions or process conditions. For this reason conservative assumptions are prevalent in practice and in many cases the protective systems become significantly oversized. From safety perspective such safety margins in venting areas can lead to a critical acceleration of the pressure rise. Moreover, a gas explosion venting at turbulent conditions caused by over sizing or by obstacles rather leads to an under-sized system. The present investigation was focused especially on the influence of certain obstacles as well as the influence of elevated initial pressures on explosion venting behaviour of quiescent hydrogen, methane or ethylene in air. T2 - 14th International symposium on loss prevention and safety promotion in the process industries CY - Florence, Italy DA - 12.05.2013 KW - Gas explosion venting KW - Turbulent combustion KW - Obstacles PY - 2013 SN - 978-88-95608-22-8 DO - https://doi.org/10.3303/CET1331111 SN - 1974-9791 N1 - Serientitel: Chemical engineering transactions – Series title: Chemical engineering transactions VL - 31 SP - 661 EP - 666 PB - AIDIC, Associazione Italiana di Ingegneria Chimica CY - Milano AN - OPUS4-28582 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Poli, Marco A1 - Grätz, Rainer A1 - Schröder, Volkmar T1 - Hazards of accelerated gas explosion venting and their safety-relevant parameters N2 - The effects of a gas explosion in enclosures like vessels can be limited e.g. by gas explosion venting systems. The major design step of this constructive explosion protection method is to determine the required vent area, which depends significantly on whether turbulent combustion exists. However, current standards like NFPA 68 or EN 14994 are applicable only to limited boundary conditions and as far as possible only to laminar flame propagation. Difficulties arise in the assessment or predictability of gas explosion hazard when turbulence occurs. In this research especially venting at elevated initial pressure has been shown to accelerated flame propagations and therefore, to a considerably higher reduced pressure. Therefore, it is essential to provide a broader data base of turbulent combustion and explosion behaviour to verify the existing rules or to determine their safety-relevant parameters. For a better safety assessment or design of protective systems the turbulent combustion and accelerated gas explosion behaviour of quiescent methane in air were investigated at initial pressures up to 8 bar using vessels up to 100 litres. In particular a systematic study was performed to investigate the influence of turbulence on the overpressure development during accelerated gas explosion. Moreover, the present study consider the position of the spark igniters, the burning velocity and the maximum pressure rise for different concentration of fuel as well as the size of orifice and/or vent area. A choice of experimental tests showed under the investigated conditions that not only turbulence inducing obstacles but also over sized vent areas could lead to an increased pressure development and therefore to an inacceptable safety state. Due to the numerous influencing variables of explosion behaviour the presented experimental results help to judge whether another more sophisticated method should be applied than the one described in standards. T2 - Hazards XXIII Symposium CY - Southport, UK DA - 12.11.2012 KW - Turbulent combustion KW - Obstacles KW - Explosion acceleration PY - 2012 SN - 978-0-85295-557-4 N1 - Serientitel: Symposium Series – Series title: Symposium Series VL - 158 IS - Paper 45 SP - 347 EP - 353 AN - OPUS4-27222 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Poli, Marco A1 - Grätz, Rainer A1 - Schröder, Volkmar T1 - An experimental study on safety-relevant parameters of turbulent gas explosion venting at elevated initial pressure N2 - The effects of a gas explosion in enclosures like vessels can be limited e.g. by gas explosion venting systems. The major design step of this constructive explosion protection method is to determine the required vent area, which depends significantly on whether turbulent combustion exists. However, current standards like NFPA 68 or EN 14994 are applicable only to limited boundary conditions and as far as possible only to laminar flame propagation. Difficulties arise in the assessment or predictability of gas explosion hazard when turbulence occurs. In this research especially venting at elevated initial pressure has been shown to accelerated flame propagations and therefore, to a considerably higher reduced pressure. Therefore, it is essential to provide a broader data base of turbulent combustion and explosion behavior to verify the existing rules or to determine their safety-relevant parameters. For a better safety assessment or design of protective systems the turbulent combustion and accelerated gas explosion behaviour of quiescent methane and hydrogen in air were investigated at initial pressures up to 8 bar using vessels up to 100 litres. In particular a systematic study was performed to investigate the influence of turbulence on the overpressure development during accelerated gas explosion. Moreover, the present study consider the position of the spark igniters, the burning velocity and the maximum pressure rise for different concentration of fuel as well as the size of orifice and/or vent area. A choice of experimental tests showed under the investigated conditions that not only turbulence inducing obstacles but also over sized vent areas could lead to an increased pressure development and therefore to an inacceptable safety state. T2 - 20th International Congress of Chemical and Process Engineering CHISA 2012 CY - Prague, Czech Republic DA - 25.08.2012 KW - Gas explosion venting KW - Turbulent combustion KW - Obstacles PY - 2012 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-264288 DO - https://doi.org/10.1016/j.proeng.2012.07.398 SN - 1877-7058 VL - 42 SP - 90 EP - 99 PB - Elsevier CY - Amsterdam AN - OPUS4-26428 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -