HySafe SBEP-V20: Numerical studies of release experiments inside a naturally ventilated residential garage

Abstract

This work presents the results of the Standard Benchmark Exercise Problem (SBEP) V20 of Work Package 6 (WP6) of HySafe Network of Excellence (NoE), co-funded by the European Commission, in the frame of evaluating the quality and suitability of codes, models and user practices by comparative assessments of code results. The benchmark problem SBEP-V20 covers reléase scenarios that were experimentally investigated in the past using helium as a substitute to hydrogen. The aim of the experimental investigations was to determine the ventilation requirements for parking hydrogen fuelled vehicles in residenKeyujords: tial garages. Helium was released under the vehicle for 2 h with 7.200 1/h flow rate. The leak Hydrogen safety rate corresponded to a 20% drop of the peak power of a 50 kW fuel cell vehicle. Three Garage double vent garage door geometries are considered in this numerical investigation. In each Reléase and dispersión simulations case the vents are located at the top and bottom of the garage door. The vents vary only in Natural ventilation height. In the first case, the height of the vents is 0.063 m, in the second 0.241 m and in the CFD third 0.495 m. Four HySafe partners participated in this benchmark. The following CFD Experiments packages with the respective models were applied to simúlate the experiments: ADREA-HF using k-s model by partner NCSRD, FLACS using k-s model by partner DNV, FLUENT using k-s model by partner UPM and CFX using laminar and the low-Re number SST model by partner JRC. This study compares the results predicted by the partners to the experimental measurements at four sensor locations inside the garage with an attempt to assess and valídate the performance of the different numerical approaches.

Natural and forced ventilation of buoyant gas released in a full-scale garage: Comparison of model predictions and experimental data

“…Concentration measurements during the release of helium underneath a wooden mock-up of an automobile placed inside a full-scale garage were reported by Swain [3]. These experiments have been simulated and substantial differences between model codes and experimental data was reported [4]. Release and dispersion in real scale enclosures using hydrogen has been reported [5] and modeled using a number of Computational Fluid Dynamics (CFD) software tools [6].…”

Emergency blower ventilation to disperse hydrogen leaking from a hydrogen-fueled vehicle

“…Papanikolaou et al [3] compared experimental and numerical results for hydrogen leakage inside a naturally ventilated garage using various codes with different models. Merilo et al [4,5] experimentally studied hydrogen leakage in a garage and also in passenger vehicle compartments.…”

CFD benchmark on hydrogen release and dispersion in confined, naturally ventilated space with one vent

“…In Ref. [15], 5 organizations carried out CFD simulations to describe the release of helium in 66 m 3 garage-like facility with 2 vents. Also in that benchmark exercise, the scattering of results was relevant e.g.…”