STATE OF THE ART AND RESEARCH PRIORITIES IN HYDROGEN SAFETY

Wide spread deployment and use of hydrogen and fuel cell technologies can occur only if hydrogen safety issues have been addressed in order to ensure that hydrogen fuel presents the same or lower level of hazards and associated risk compared to conventional fuel technologies. To achieve this goal, hydrogen safety research should be directed to address the remaining knowledge gaps using risk-informed approaches to develop engineering solutions and Regulation Codes and Standards (RCS) requirements that meet individual and societal risk acceptance criteria, yet are cost-effective and market-competitive. IA HySafe and JRC IET partnered to organize a Research Priorities Workshop in Berlin on October 16-17, 2012 hosted by BAM (on behalf of IA HySafe) to address knowledge gaps in CFD modelling of hydrogen safety issues. The findings of the workshop are described in the report. The document aims to become a reference document for researchers/scientists and technical (including industry) experts working in the area worldwide. It is also a welcomed contribution for the Fuel Cell and Hydrogen Joint Undertaking (FCH JU) and for other funding bodies/organizations that must make decisions on research programmes and during the selection/choice of projects to be financially supported pursuing the safe use of hydrogen within Horizon 2020 framework.JRC.F.2-Energy Conversion and Storage Technologie

Gap Analysis of CFD Modelling of Accidental Hydrogen Release and Combustion

The report describes the findings of a workshop that was held at the Institute for Energy (JRC) in Petten Netherlands, on the topic "Gap analysis of CFD modelling of hydrogen release and combustion". The main topic was divided in 6 sub-topics: release and dispersion, auto-ignition, fires, deflagrations, detonations and DDT, and accident consequences. For each sub-topic, the main gaps in CFD modelling were identified and prioritised.JRC.DDG.F.2-Cleaner energ

Prioritisation of Research and Development for modelling the safe production, storage, delivery and use of hydrogen.

Hydrogen is expected to play an important role in the energy mix of a future low carbon society, (the European Strategic Energy Technology Plan of the European Commission (COM 2007 - 723) and in the Hydrogen, Fuel Cells & Infrastructure Technologies Program-Multi-Year Research, Development, and Demonstration Plan of the USA Department of Energy (DoE 2007). Hydrogen safety issues must be addressed in order to ensure that the wide spread deployment and use of hydrogen and fuel cell technologies can occur with the same or lower level of hazards and associated risk compared to the conventional fossil fuel technologies. Hydrogen safety is a EU Policy relevant issue as it is stated in the priority 3 Action 2 (Continuous improvement in safety and security) of the EU “Energy 2020 A strategy for competitive, sustainable and secure energy”: “The same security and safety considerations will also be upheld in the development and deployment of new energy technologies (hydrogen safety, safety of CO2 transportation network, CO2 storage, etc…)” Computational Fluid Dynamics (CFD) is one of the tools to investigate safety issues related to the production, storage, delivery and use of hydrogen. CFD techniques can provide a wealthy amount of information on the dynamics of hypothetical hydrogen accident and its consequences. The CFD-based consequence analysis is then used in risk assessments. This report describes the output of a workshop organised at the Institute for Energy and Transport (JRC) in Petten, Netherlands to identify the gaps and issues in CFD modelling of hydrogen release and combustion. A hydrogen accident usually follows a typical sequence of events: an unintended release, the mixing of hydrogen with air to form a flammable mixture, the ignition of the flammable cloud and depending on the conditions, and a fire or an explosion (deflagration or/and detonation). For each stage of the accident, the critical CFD issues have been identified and prioritised. Beyond the specific issues of CFD modelling that are described for each accident stage in the report, some general modelling issues can be found in all stages: • lack of an extensive validation of CFD codes/models that covers all the relevant range of conditions that can be found in hypothetical accident scenarios e.g. in terms of geometrical lay-out, leak flow rates. • lack of a CFD validation protocol for hydrogen like it exists for Liquefied Natural Gas (LNG): the Model Evaluation Protocols (MEP) for assessment of models for accident consequences, with guidance on evaluating models in terms of scientific assessment, verification and validation. • lack of a database of experiments for validation of hydrogen models. • in some cases, lack of complete and accurate experimental data for the CFD validation. The goals of this work were to perform a state of the art review in CFD modelling of hypothetical accidents scenarios related to hydrogen technologies and identify and prioritise the gaps in the field. The report is based on a dedicated workshop organised in Petten with the participation of external experts an extensive literature review performed by experts in the field and the direct expertise and experience of the experts. The experts were carefully selected according to their experience/expertise, number of scientific publications and participations to International Conferences, seminars, workshops and to international and/or European co-funded projects such as HySafe (Hydrogen Safety), HyApproval (Approval of Hydrogen Re-fuelling Stations), European Integrated Hydrogen Projects. By performing a state of the art review of CFD modelling for hydrogen safety issues, a consensus was reached among the scientific experts as to the main gaps in the field and on the priority of the research needs.JRC.F.2-Cleaner energ