Canada

We present results from hydrogen dispersion simulations from a pressurized reservoir at constant flow rate in the presence and absence of a wall. The dispersion simulations are performed using a commercial finite volume solver. Validation of the approach is discussed. Constant concentration envelopes corresponding to the 2% 4% and 15% hydrogen concentration in air are calculated for a subcritical vertical jet and for an equivalent subcritical ho Read More

A potentially viable solution to the problem of greenhouse gas emissions by vehicles in the transportation sector is the deployment of hydrogen as alternative fuel. A limitation to the diffusion of the hydrogen‐fuelled vehicles option is the intricate refuelling stations that vehicles will require. This study examines the practical use of hydrogen fuel within the internal combustion engine (ICE)‐powered long‐haul heavy‐duty trucking vehicles. Specifically it appraises Read More

In this paper a vertical turbulent round jet of helium was studied numerically using the PHOENICS software package. The flow was assumed to be steady incompressible and turbulent. The jet discharge Froude number was 14000 and the turbulent Schmidt number was 0.7. The incompressible Reynolds average Navier-Stokes equations and helium transport equation expressed in 2-D axisymmetric domain were applied to model the underlying helium relea Read More

The integration of a hydrogen gas storage arrangement in vehicles has not been without its challenges. Gaseous state of hydrogen at ambient temperature combined with the fact that hydrogen is highly flammable results in the requirement of more robust high pressure storage systems that can meet modern safety standards. To develop these new safety standards and to properly predict the phenomena of hydrogen dispersion a better understanding of Read More

This paper discusses the results of computational fluid dynamics (CFD) modelling of hydrogen releases and dispersion outdoors during venting of hydrogen storage in real environment and geometry of a hydrogen refuelling or energy station for a given flow rate and dimensions of vent stack. The PHOENICS CFD software package was used to solve the continuity momentum and concentration equations with the appropriate boundary conditions buoyancy Read More

Photocatalysis for “green” hydrogen production is a technology of increasing importance that has been studied using both TiO2–based and heterojunction composite-based semiconductors. Different irradiation sources and reactor units can be considered for the enhancement of photocatalysis. Current approaches also consider the use of electron/hole scavengers organic species such as ethanol that are “available” in agricultural waste in commu Read More

Previous experiments demonstrated that the accidental release of high pressure hydrogen into air can lead to the possibility of spontaneous ignition. It is believed that this ignition is due to the heating of the mixing layer between hydrogen and air that is caused by the shock wave driven by the pressurized hydrogen during the release. Currently this problem is poorly understood and not amenable to direct numerical simulation. This is due to the pres Read More

The scenario of ignition of fuels by the passage of shock waves is relevant from the perspective of safety primarily because shock ignition potentially plays an important role in deflagration to detonation transition. Even in one dimension simulation of ignition between a contact surface or a flame and a shock moving into combustible mixture is difficult because of the singular nature of the initial conditions. Indeed initially as the shock starts moving away from th Read More

Today in order to reduce the increase of the carbon dioxide emissions a large number of renewable energy resources (RES) are already implemented. Considering both the intermittency and uncertainty of the RES the energy storage system (ESS) is still needed for balancing and stabilizing the power system. Among different existing categories of ESS the hydrogen storage systems (HSS) have the highest energy density and are crucial for the RES integr Read More

With the simple structure and quick refuelling process the compressed hydrogen storage system is currently widely used. However thermal effects during charging-discharging cycle may induce temperature change in storage tank which has significant impact on the performance of hydrogen storage and the safety of hydrogen storage tank. To address this issue we once propose a single zone lumped parameter model to obtain the analytical solution of Read More