Papers by Alessia Marangon
La presente tesi di dottorato presenta gli apetti di sicurezza delle miscele idrogeno / metano. L... more La presente tesi di dottorato presenta gli apetti di sicurezza delle miscele idrogeno / metano. La parte teorica ha riguardato lo studio delle tecniche di misura delle concentrazione delle miscele con aggiunta di idrogeno fino ad un 30%vol. in metano. Attività sperimentali di rilascio e stratificazione in ambiente chiuso ed in ambiente dotato di ventilazione naturale sono state condotte presso il laboratorio del Dipartimento. Le concentrazioni sono state misurate con l'ausilio di sensori ossigeno e gas cromatigrafia. Simulazioni CFD sono state condotte per la verifica della riproducibilità delle caratteristiche di dispersione e stratificazione delle suddette miscele
A method for determination of hazardous zones for hydrogen installations has been studied. This w... more A method for determination of hazardous zones for hydrogen installations has been studied. This work has been carried out within the NoE HySafe. The method is based on the Italian Method outlined in Guide 31-30(2004), Guide 31-35(2001), Guide 31-35/A(2001), and Guide 31-35/A; V1(2003). Hazardous zones for a "generic hydrogen refuelling station"(HRS) are assessed, based on this method. The method is consistent with the EU directive 1999/92/EC "Safety and Health Protection of Workers potentially at risk from explosive atmospheres" which is the basis for determination of hazardous zones in Europe. This regulation is focused on protection of workers, and is relevant for hydrogen installations, such as hydrogen refuelling stations, repair shops and other stationary installations where some type of work operations will be involved. The method is also based on the IEC standard and European norm IEC/EN60079-10 "Electrical apparatus for explosive gas atmospheres. Par...
International Journal of Hydrogen Energy, 2016
Users may download and print one copy of any publication from the public portal for the purpose... more Users may download and print one copy of any publication from the public portal for the purpose of private study or research. You may not further distribute the material or use it for any profit-making activity or commercial gain You may freely distribute the URL identifying the publication in the public portal If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.
Developing a future sustainable refuelling station network is the next important step to establis... more Developing a future sustainable refuelling station network is the next important step to establish hydrogen as a fuel for vehicles and related services. Such stations will most likely be integrated in existing refuelling stations and result in multi-fuel storages with a variety of fuels being delivered, stored and distributed, as e.g. biomass based methane, ethanol, gasoline, diesel as well as the traditional crude oil based products. Hydrogen is also in play as intermediate energy storage to secure the power supply based on large shares of fluctuating energy sources and as an intermediate to improve the quality of biomass based fuels. Therefore, hydrogen supply and distribution chains will likely not only serve to fulfil the demands of refuelling, but may also be important for the wider electrical power and fuel industries. Based on an integrated hydrogen supply and distribution network, the application of the method of “Functional modelling” is discussed in this paper to show the ...
International Journal of …, 2010
to identify exactly which assumptions and parameters were responsible for the differences in resu... more to identify exactly which assumptions and parameters were responsible for the differences in results. These results provided the basis for a more guided QRA, the second phase. This phase 2 was defined in which the QRA was determined by a more limited number of release cases (scenarios). The partners in the project agreed to assess specific scenarios in order to identify the differences in consequence assessment approaches. The results of this phase provide a better understanding of the influence of modelling assumptions and limitations on the eventual conclusions with regard to risk to on-site people and to the off-site public.
CFD Simulations a b s t r a c t Within the framework of the internal project HyQRA of the HYSAFE ... more CFD Simulations a b s t r a c t Within the framework of the internal project HyQRA of the HYSAFE Network of Excellence (NoE), funded by the European Commission (EC), the participating partners were requested to apply their Quantitative Risk Assessment (QRA) methodologies on a predefined hypo-thetical gaseous H 2 refuelling station named BBC (Benchmark Base Case). The overall aim of the HyQRA project was to perform an inter-comparison of the various QRA approaches and to identify the knowledge gaps on data and information needed in the QRA steps specifically related to H 2 . Partners NCSRD and UNIPI collaborated on a common QRA. UNIPI identified the hazards on site, selected the most critical ones, defined the events that could be the primary cause of an accident and provided to NCSRD the scenarios listed in risk order for the evaluation of the consequences. NCSRD performed the quantitative analysis using the ADREA-HF CFD code. The predicted risk assessment parameters (flammable H 2 ...
International Journal of Hydrogen Energy, 2014
ABSTRACT Experiments were carried out inside a 25 m3 vented combustion test facility (CVE) with a... more ABSTRACT Experiments were carried out inside a 25 m3 vented combustion test facility (CVE) with a fixed vent area sealed by a plastic sheet vent. Inside the CVE, a 0.64 m3 open vent box, called RED-CVE was placed. The vent of the RED-CVE was left open and three different vent area were tested. Two different mixing fans, one for each compartment, were used to establish homogeneous H2 concentrations. This study examined H2 concentrations in the range between 8.5% vol. to 12.5% vol. and three different ignition locations, (1) far vent ignition, (2) inside the RED-CVE box ignition and (3) near vent ignition (the vent refers to the CVE vent). Peak overpressures generated inside the test facility and the smaller compartment were measured. The results indicate that the near vent ignition generates negligible peak overpressures inside the test facility as compared to those originated by far vent ignition and ignition inside the RED-CVE box. The experiments with far vent ignition showed a pressure increase with increasing hydrogen concentration which reached a peak value at 11% vol. concentration and then decreased showing a non-monotonic behaviour. The overpressure measured inside the RED-CVE was higher when the ignition was outside the box whereas the flame entered the box through the small vent.
International Journal of Hydrogen Energy, 2011
Quantitative Risk Assessment Consequence assessment Refuelling station CFD Simulations a b s t r ... more Quantitative Risk Assessment Consequence assessment Refuelling station CFD Simulations a b s t r a c t Within the framework of the internal project HyQRA of the HYSAFE Network of Excellence (NoE), funded by the European Commission (EC), the participating partners were requested to apply their Quantitative Risk Assessment (QRA) methodologies on a predefined hypothetical gaseous H 2 refuelling station named BBC (Benchmark Base Case). The overall aim of the HyQRA project was to perform an inter-comparison of the various QRA approaches and to identify the knowledge gaps on data and information needed in the QRA steps specifically related to H 2 . Partners NCSRD and UNIPI collaborated on a common QRA. UNIPI identified the hazards on site, selected the most critical ones, defined the events that could be the primary cause of an accident and provided to NCSRD the scenarios listed in risk order for the evaluation of the consequences. NCSRD performed the quantitative analysis using the ADREA-HF CFD code. The predicted risk assessment parameters (flammable H 2 mass and volume time histories and maximum horizontal and vertical distances of the LFL from the source) were provided to UNIPI to analyze the consequences and to evaluate the risk and distances of damage. In total 15 scenarios were simulated. Five of them were H 2 releases in confined ventilated spaces (inside the compression and the purification/drying buildings). The remaining 10 scenarios were releases in open/semi-confined spaces (in the storage cabinet, storage bank and refuelling hose of one dispenser). This paper presents the CFD methodology applied for the quantitative analysis of the common UNIPI/NCSRD QRA and discusses the results obtained from the performed calculations. (E. Papanikolaou).
Explosion Vent CFD a b s t r a c t The CVE (Chambre View Explosion) is an experimental facility o... more Explosion Vent CFD a b s t r a c t The CVE (Chambre View Explosion) is an experimental facility owned by the DIMNP at the University of Pisa ''Scalbatraio'' laboratory to study the confined vented explosion phenomena in real environments. The CVE is a cubic apparatus of 25 m 3 , equipped with two glass walls that enable to video record the explosion and the flame expansion, and the relevant path. The experimental campaign and the results here presented were focused on the investigation of the turbulence induced by obstacles on the vented deflagration for homogeneous conditions of concentration. For this purpose two sets of obstacles constituted by plates were designed and put inside the apparatus. Besides the experimental activities, also a modelling work has been carried out with the CFD code FLACS V8.1 (FLame ACceleration Simulator) in order to predict and reproduce the turbulent confined hydrogen vented explosion. A comparison between the experimental video recorded data and the same data reproduced through the CFD simulations is presented. ª (A. Marangon). A v a i l a b l e a t w w w . s c i e n c e d i r e c t . c o m j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / h e
International Journal of Hydrogen Energy, 2007
In order to facilitate the introduction of a new technology, as it is the utilization of hydrogen... more In order to facilitate the introduction of a new technology, as it is the utilization of hydrogen as an energy carrier, development of safety codes and standards, besides the conduction of demonstrative projects, becomes a very important action to be realized. Useful tools of work could be the existing gaseous fuel codes (natural gas and propane) regulating the stationary and automotive applications. Some safety codes have been updated to include hydrogen, but they have been based on criteria and/or data applicable for large industrial facilities making the realization of public hydrogen infrastructures prohibitive in terms of space. In order to solve the above mentioned problems, others questions come out: how these safety distances have been defined? Which hazard events have been taken as reference for calculation? Is it possible to reduce the safety distances through an appropriate design of systems and components, or through the predisposition of adequate mitigation measures? This paper presents an analysis of the definitions of "safety distances" and "hazardous locations", as well as a synoptic analysis of the different values in force in several States for hydrogen and natural gas. The above mentioned synoptic table will highlight the lacks and so some fields that need to be investigated in order to produce a suitable hydrogen standard.
International Journal of Hydrogen Energy, 2011
Refuelling station a b s t r a c t A benchmarking exercise on quantitative risk assessment (QRA) ... more Refuelling station a b s t r a c t A benchmarking exercise on quantitative risk assessment (QRA) methodologies for hydrogen safety has been conducted within the project HyQRA, under the framework of the European Network of Excellence (NoE), HySafe. The aim of the exercise was twofold: (i) to identify the differences and similarities in approaches in a QRA and their results for a hydrogen installation and (ii) to identify knowledge gaps in the various steps and parameters underlying the risk quantification of hydrogen safety.
Experimental activities a b s t r a c t
International Journal of Hydrogen Energy, Apr 27, 2010
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Papers by Alessia Marangon