The testing provided data to allow the ability of Computational Fluid Dynamics (CFD) modelling to predict accumulation of natural gas from transient releases and temporal and spatial variations in explosion loading. Strain and pressure data was also gained on the structural response to allow assessment of structural modelling. 

Hydrogen is a key energy carrier for modern society. The breaking of the hydrogen bonds within traditional hydrocarbon molecules has been the primary mode of energy utilization since the industrial revolution. An increased focus on “net-zero” greenhouse gas emissions, specifically carbon dioxide and methane, has resulted in a global push for lower carbon energy vectors, including pure hydrogen.

Natural gas distribution companies are developing ambitious plans to decarbonize the services that they provide in an affordable manner and are accelerating plans for the strategic integration of renewable natural gas and the blending of green hydrogen produced by electrolysis, powered with renewable electricity being developed from large new commitments by states such as New York and Massachusetts. The demonstration and deployment of hydrogen blending have been proposed broadly at 20% of hydrogen by volume.

An under-expanded hydrogen jet from high-pressure equipment or storage tank is a potential incident scenario. Experiments demonstrated that the delayed ignition of a highly turbulent under-expanded hydrogen jet generates a blast wave able to harm people and damage property. There is a need for engineering tools to predict the pressure effects during such incidents to define hazard distances. The similitude analysis is applied to build a correlation using available experimental data.

Mixing of hydrogen into natural gas, as a means of mitigating environmental concerns associated with the use of fossil fuels, poses a question of performance of appliances designed for use with natural gas, when fuelled by blends of hydrogen and natural gas. This study examines the performance of space and water heating appliances fuelled by methane as a natural gas proxy, and methane/hydrogen blends containing up to 15% hydrogen.

The ignition of a hydrogen-air mixture that has engulfed a typical set of ambient vaporizers (i.e., an array of finned tubes) may result in a deflagration-to-detonation transition (DDT). Simplified curve-based vapor cloud explosion (VCE) blast load prediction methods, such as the Baker-Strehlow-Tang (BST) method, would predict a DDT given that typical ambient vaporizerswould be rated as medium or high congestion and hydrogen is a high reactivity fuel (i.e., high laminar burning velocity).

Ammonia and hydrogen represent opposite ends of the spectrum with regard to the potential blast loading resulting from an accidental vapor cloud explosion (VCE), although many in industry have expressed doubts as to whether either of these fuels actually pose a VCE hazard. Ammonia is some-times discounted as a VCE hazard due to the perceived difficulty in igniting an ammonia-air mixture and/or because of its low laminar burning velocity. Hydrogen is sometimes discounted as a VCE hazard due to the ease with which a hydrogen-air mixture can be ignited and/or because of its buoy-ancy.

The aim of the present work is to assess the risk of explosion in closed containments used for the transportation of nuclear materials or nuclear waste. Indeed, it is very well known that hydrogen can be produced due to (i) the radiolysis of different materials within the containment, (ii) the thermal decomposition of mainly the organic part in the containment. Since hydrogen has a very low ignition energy and a very wide flammability domain, it is important to determine the risk of ignition of the subsequent mixture produced by the aforementioned mechanisms.

AS THE WORLD SEEKS TO IDENTIFY alternative energy sources, hydrogen-powered fuel cells offer a broad range of benefits for the environment, the economy, and energy security. Hydrogen fuel cells have the potential to replace the internal combustion engine and to provide power in a wide range of stationary and portable applications.

Owner/operators of chemical processing and petroleum refining sites often ask whether unconfined hydrogen vapor cloud explosions (VCEs) can actually occur. This question normally arises during the course of a consequence-based facility siting study (FSS) or a quantitative risk assessment (QRA). While it is generally recognized that a hydrogen release within a process enclosure could lead to an explosion, the potential for an external hydrogen release to cause a VCE is not as widely recognized and is often questioned.