Browse

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 ...

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...

The study of hydrogen explosions in interconnected spaces is essential for safety in industrial and laboratory settings. Due to its highly flammable nature, understanding hydrogen explosion dynamics is essential for risk mitigation. This paper presents an experimental and computational analysis of a hydrogen explosion in a setup with four interconnected chambers. The experimental stand had transparent walls for direct observation. Ignition was initiated to analyze flame propagation, acceleration, and pressure vari...

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...

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...

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...

The identification technique of hazardous clouds using infrared spectrometry is based on the spectral analysis of electromagnetic radiation that is absorbed and emitted by the molecules of a gas cloud. Molecules can be identified by analyzing the location of lines inside the spectrum, representing the energy differences between the cases involved and the strength of the lines, which is the probability of a photon being absorbed or emitted. This method is often called passive infrared spectrometry because no artifi...

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...

The cause of the explosion is the thermal energy delivered by the flammable/ fuel ignition source. The action of the ignition source on the flammable medium can be direct or indirect. The most common of the direct sources of ignition are open flames and electric and mechanical sparks. These sources release their energy into the environment, which, if it contains flammable substances in appropriate proportions, is initiated. This is followed by a chain of fuel oxidation reactions and by the propagation of a flame f...