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In the context of the transition to a hydrogen-based economy, the assessment of the risks associated with this energy vector is becoming a priority for industrial safety. The unique properties of hydrogen, its high reactivity and high burning rate, require the use of advanced numerical simulation tools, capable of providing highly accurate predictions of the effects of explosive phenomena. This paper presents methodological contributions aimed at optimizing the numerical models used for the analysis of explosions ...

This paper presents the design and numerical analysis of an experimental system intended to study the effects of water curtains on the propagation of hydrogen explosions. The developed virtual model reproduces a test stand consisting of three successive chambers separated by two water-filled barriers acting as water curtain obstacles. The atmosphere in the chambers is composed of an explosive hydrogen–air mixture with a hydrogen concentration of 25%. The explosion is initiated in the first chamber, and the propa...

The present paper presents the transfer to the virtual environment and CFD analysis of physical experiments on the explosions of air-hydrogen mixtures carried out on a transparent stand, in the shape of a rectangular spiral. The shape of the stand was designed with the intention of directing the explosion process of the fuel mixture on a rectangular-spiral trajectory, with angles of 90 degrees. The free volume inside the spiral was sectioned by four foiled shutters into four ignition/combustion chambers, the first...

Hydrogen, known for its high flammability and potential explosive characteristics, presents significant challenges in safety engineering, particularly in enclosed spaces where explosions can lead to catastrophic consequences. This paper presents the results of physical experiments conducted to investigate the linear propagation of hydrogen explosions within confined environments. The experiments were designed to simulate real-world scenarios and assess the factors influencing the extent and characteristics of expl...

Risks are present in all economic and industrial activities that manifest themselves both through economic losses, malfunctions of installations and equipment, as well as the occurrence of minor or major accidents with particularly serious consequences resulting in deaths and injuries, pollution of the environment. The assessment of risk levels stimulates the co-interest of economic operators to improve their working and environmental conditions, respectively to take measures to move from high risk levels to lower...

Hydrogen explosions can occur in industrial processes, in laboratories, in hydrogen production and storage processes, or in new combustion processes used in modern transportation. This gas presents a particularly dangerous potential due to its flammability properties. The combustion reaction of this gas mixed with air or oxygen is strongly exothermic, resulting in a rapid increase in temperatures and pressures developed. When these overpressures become too great to be supported by the vessels or enclosures where t...

The use of natural gas as a home heating source has, unfortunately, generated a number of gas explosion events, most of which have as their main cause the accidental leakage of combustible gas. The dynamic effects generated by the explosion pressures differ from case to case, depending on the concentrations of combustible gas accumulated in the chambers from the time of the occurrence of the gas leak to the occurrence of the source of initiation. Often, these dynamic effects involve concentrations close to the sto...

In the investigation of gas explosion events resulting from combustible gas leakage, often the formation of the explosive atmosphere at the location of the ignition source is less highlighted, usually being calculated the concentration of combustible gases at the entire volume affected by the explosion; depending on the distance between the gas source and the ignition, the complexity of the geometry (volumes occupied by various solid bodies) and the air currents in that volume (convective currents generated by hea...

Most of the time, in assessing a situation where a leakage of combustible gas is involved, the volume of the room where the release occurs and the volume of the released gas is taken into account, thus resulting in an average concentration of the fuel gas applied to the entire volume of the room. In some cases, when the source of combustible gas is close enough to the source of initiation, or when air currents converge at the location of the source of initiation carrying amounts of combustible gas, the explosive m...

Methane gas, one of the underground mine atmosphere, is the main hazard for the workers in this field. The risk of occurrence of an explosive atmosphere and the consequences are different from one mine to another, based on the mine type, its configuration, the extracted coal and the probability of the methane and coal dust occurrence. With every prevention measure taken, the potential risk of an explosion cannot be excluded from the firedamp mines, just reduced as much as possible. The controlled researches regard...

Regarding the mining industry, the risk of an explosive atmosphere occurrence and the consequences differ from one mine to another, depending on the configuration of the mine and on the type of the coal extracted. Although preventive measures are taken, the potential risk of explosion cannot be excluded from firedamp mines, but only reduced as much as possible. Therefore, where the possibility of forming these explosive atmospheres exists, the explosion risk assessment is required by developing scenarios that cons...