Numerical study on the influence of different boundary conditions on the efficiency of hydrogen recombiners inside a car garage

التفاصيل البيبلوغرافية
العنوان: Numerical study on the influence of different boundary conditions on the efficiency of hydrogen recombiners inside a car garage
المؤلفون: Hans-Josef Allelein, Ernst Arndt Reinecke, J. Baggemann, Stephan Kelm, W. Jahn
المصدر: International Journal of Hydrogen Energy. 42:7608-7616
بيانات النشر: Elsevier BV, 2017.
سنة النشر: 2017
مصطلحات موضوعية: Hydrogen, Renewable Energy, Sustainability and the Environment, business.industry, Nuclear engineering, 05 social sciences, Energy Engineering and Power Technology, chemistry.chemical_element, System safety, 02 engineering and technology, Computational fluid dynamics, Ceiling (cloud), 021001 nanoscience & nanotechnology, Condensed Matter Physics, Fuel Technology, Hydrogen safety, chemistry, Homogeneous, 0502 economics and business, Vertical direction, Environmental science, Boundary value problem, 050207 economics, 0210 nano-technology, business
الوصف: Passive auto-catalytic recombiners (PARs) have the potential to be used in the future for the removal of accidentally released hydrogen inside confined areas. PARs could be operated both as stand-alone or backup safety devices, e.g. in case of active ventilation failure. Recently, computational fluid dynamics (CFD) simulations have been performed in order to demonstrate the principal performance of a PAR during a postulated hydrogen release inside a car garage. This fundamental study has now been extended towards a variation of several boundary conditions including PAR location, hydrogen release scenario, and active venting operation. The goal of this enhanced study is to investigate the sensitivity of the PAR operational behavior for changing boundary conditions, and to support the identification of a suitable PAR positioning strategy. For the simulation of PAR operation, the in-house code REKO-DIREKT has been implemented in the CFD code ANSYS-CFX 15. In a first step, the vertical position of the PAR and the thermal boundary conditions of the garage walls have been modified. In a subsequent step, different hydrogen release modes have been simulated, which result either in a hydrogen-rich layer underneath the ceiling or in a homogeneous hydrogen distribution inside the garage. Furthermore, the interaction of active venting and PAR operation has been investigated. As a result of this parameter study, the optimum PAR location was identified to be close underneath the garage ceiling. In case of active venting failure, the PAR efficiently reduces the flammable gas volume (hydrogen concentration > 4 vol.%) for both stratified and homogeneous distribution. However, the simulations indicate that the simultaneous operation of active venting and PAR may in some cases reduce the overall efficiency of hydrogen removal. Consequently, a well-matched arrangement of both safety systems is required in order to optimize the overall efficiency. The presented CFD-based approach is an appropriate tool to support the assessment of the efficiency of PAR application for plant design and safety considerations with regard to the use of hydrogen in confined areas.
تدمد: 0360-3199
DOI: 10.1016/j.ijhydene.2016.04.084
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_________::61ca845394538bca815817aa588bfa4a
https://doi.org/10.1016/j.ijhydene.2016.04.084
Rights: CLOSED
رقم الانضمام: edsair.doi...........61ca845394538bca815817aa588bfa4a
قاعدة البيانات: OpenAIRE