Advanced computational fluid dynamics (CFD) models of gas release and dispersion (GRAD) have been developed, tested, validated and applied to the modeling of various industrial real-life indoor and outdoor flammable gas (hydrogen, methane, etc.) release scenarios with complex geometries. The user-friendly GRAD CFD modeling tool has been designed as a customized module based on the commercial general-purpose CFD software, PHOENICS.
Integrated multi-channel nano-engineered optical hydrogen and temperature sensor detection systems for launch vehicles
Launch vehicles and other satellite users need launch services that are highly reliable, less complex, easier to test, and cost effective. Being a very small molecule, hydrogen is prone to leakage through seals and micro-cracks. Hydrogen detection in space application is very challenging; public acceptance of hydrogen fuel would require the integration of a reliable hydrogen safety sensor.
A reusable launch vehicle is one of the low-cost rocket launch system concepts suitable for large-scale space transportation, such as construction of solar power satellites and space tourism for the general public. From the result of studying "Kankoh-maru," the RLV design for space tourism, it is found that one RLV is required to be launched once a day for a successful commercial service. This means that the turn-around time for RLVs must be much shorter than that for existing expendable rockets, whose launch rate is a few times per year.
Several materials issues and challenges exist for the use of hydrogen in energy applications and form the basis for hydrogen R&D in Canada. Many of the challenges are similar for both domestic and defence applications, but there are several unique end-use requirements. In military applications the overall system should have highest energy density possible and reliably deliver for the duration of the required mission. For high energy density, this means the more hydrogen per unit weight and/or volume that can be generated, stored or carried, the better.
This report discusses the use of small cryogenic coolers for cooling the Muon Ionization Cooling Experiment (MICE) liquid cryogen absorbers. Since the absorber must be able contain liquid helium as well liquid hydrogen, the characteristics of the available 4.2 K coolers are used here. The issues associated with connecting two-stage coolers to liquid absorbers are discussed. The projected heat flows into an absorber and the cooldown of the absorbers using the cooler are presented. The warm-up of the absorber is discussed.
Research into the performance of proton exchange membrane fuel cell (PEMFC) and its degradation ("poisoning") by the presence of carbon monoxide, a common byproduct of most common hydrogen production methods, requires storage of a large quantities of hydrogen/carbon monoxide mixture in high pressure tanks. The possibility of unintended release of the gas calls for a safety study of H-2/CO mixture leaks, as well as potential higher rate releases.
Hydrogen energy offers great promise as an energy alternative. Hydrogen technologies can reduce and eliminate the release of carbon dioxide from fossil-fuel combustion, the main cause of global warming. One of the main challenges is hydrogen storage. Storing hydrogen in the solid-state hydride form holds a volumetric advantage over compressed and liquid hydrogen states.
The generation of hydrogen-gas from metallic waste is an important issue for the safety analysis of geological disposal facilities for transuranic (TRU) radioactive waste in Japan. The objective of this study is to clarify the gas-generation behavior of stainless steel and carbon steel in non-oxidizing alkaline synthetic groundwater (pH 12.8 and 10.5) at 30 degrees C simulating geological disposal environments.
For safety reasons, while handling fuel cells, hydrogen concentrations of 0.1 - 3%2and above need to be detected. Low power hydrogen sensors, based on a Field Effect Transistor (FET), have been in use for about 25 years. In the past platinum and palladium were often used as gas sensitive layers. Unfortunately in the required concentration range, the Pt based sensors have a poor selectivity at room temperature and were not stable at operating temperatures above 60 degrees C.
Fuel cell bus with hydrogen tanks on its roof is different from traditional one. Its mass is greater than traditional one and its centre of gravity is higher, which makes its rollover more easy and dangerous. During the rollover, the great deformation of the body structure will menace the occupants' safety, and in addition, the hydrogen leaking will threaten the lives of the occupants. So measures should be taken to ensure the deformation of body structure would not hurt the Occupants, and the hydrogen pipelines would not have gas leakage.