Search

Objective The applicability of current China's natural gas analysis and testing standards under hydrogen-blended conditions needs to be confirmed ed to promote the standardization of hydrogen-blended natural gas. Methods By analyzing China's natural gas analysis and testing standards, 10 standards related to hydrogen-blended natural gas have been selected and the applicability of natural gas composition analysis standards and physical property calculation standards under hydrogen-blended conditions has been studied. Results The results show that the maximum hydrogen concentration specified by the natural gas composition analysis standard represented by GB/T 13610-2020 Analysis of natural gas composition-Gas chromatography and the physical property calculation standard represented by GB/T 17747.2-2011 Natural gas-Calculation of compression factor- Part 2: Calculation using molar-composition analysis is 10%, and the relevant standards need to be revised under the condition of high hydrogen concentration. Besides, if the hydrogen is not separated downstream, the interchangeability of natural gas and its standardization need to be studied urgently. Conclusions The proposed formulation and revision framework has reference significance for the future standardization work of hydrogen-blended natural gas. [ABSTRACT FROM AUTHOR]

The development of a hydrogen energy-based society is becoming the solution for more and more countries. Fuel cell electric vehicles are the best carriers for developing a hydrogen energy-based society. The current research on hydrogen leakage and the diffusion of fuel cell electric vehicles has been sufficient. However, the study of hydrogen safety has not reduced the safety concerns for society and government management departments, concerning the large-scale promotion of fuel cell electric vehicles. Hydrogen safety is both a technical and psychological issue. This paper aims to provide a comprehensive overview of fuel cell electric vehicles' hydrogen dispersion and the burning behavior and introduce the relevant work of international standardization and global technical regulations. The CFD simulations in tunnels, underground car parks, and multistory car parks show that the hydrogen escape performance is excellent. At the same time, the research verifies that the flow, the direction of leakage, and the vehicle itself are the most critical factors affecting hydrogen distribution. The impact of the leakage location and leakage pore size is much smaller. The relevant studies also show that the risk is still controllable even if the hydrogen leakage rate is increased ten times the limit of GTR 13 to 1000 NL/min and then ignited. Multi-vehicle combustion tests of fuel cell electric vehicles showed that adjacent vehicles were not ignited by the hydrogen. This shows that as long as the appropriate measures are taken, the risk of a hydrogen leak or the combustion of fuel cell electric vehicles is controllable. The introduction of relevant standards and regulations also indirectly proves this point. This paper will provide product design guidelines for R&D personnel, offer the latest knowledge and guidance to the regulatory agencies, and increase the public's acceptance of fuel cell electric vehicles. [ABSTRACT FROM AUTHOR]