Article
Chemistry, Physical
Thanh Tuan Nguyen, Kyung-Oh Bae, Park Jaeyeong, Seung Hoon Nahm, Un Bong Baek
Summary: There is no common standard for blended hydrogen use in the natural gas grid. The need for quantitative evaluation of hydrogen-natural gas mixtures to ensure the mechanical performance of pipeline structures is becoming increasingly evident. This study provides experimental data on the effect of H-2 concentration in a methane/hydrogen gas mixture and compares the mechanical performance of three pipeline steels.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Chen Wang, Dengji Zhou, Wang Xiao, Chongyuan Shui, Tao Ma, Peng Chen, Jiarui Hao, Jun Yan
Summary: Hydrogen energy, with its advantages of renewable, clean, and high energy density, is regarded as the most potential secondary energy in the 21st century. However, transportation remains a major constraint on hydrogen development. Injecting hydrogen into the natural gas network for transport is a possible solution, but the differences in properties between natural gas and hydrogen necessitates the establishment of a natural gas pipeline model to explore the influence of hydrogen on pipeline dynamics. The line-pack of the natural gas network plays a crucial role in the system's flexibility and response to external conditions. The study showed that the line-pack affects the dynamic characteristics of the network when hydrogen is injected, with the response speed of hydrogen mixture ratio being faster under low line-pack conditions, benefiting the reduction of hydrogen embrittlement risks.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Physical
Zihang Zhang, Isam Saedi, Sleiman Mhanna, Kai Wu, Pierluigi Mancarella
Summary: The study presents a transient analysis model for tracking gas compositions and hydrogen fractions in meshed networks with multiple NG and intermittent hydrogen sources. By introducing a time-varying compressibility factor and numerical techniques, the method effectively addresses the decarbonization challenges in natural gas systems with hydrogen blending.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Mathematics
Qiang Wang, Pyeoungkee Kim, Wenzhen Qu
Summary: A hybrid localized meshless method is developed for solving transient groundwater flow in two dimensions by combining the Crank-Nicolson scheme and the generalized finite difference method. The method shows good accuracy and convergence.
Article
Energy & Fuels
Bonchan Koo
Summary: This study analyzes and compares two numerical methods for modeling transient flow in a single natural-gas pipeline. The pressure-based finite-volume method with the TVD scheme outperforms the conventional implicit method of characteristics for both slow and fast transient problems.
JOURNAL OF NATURAL GAS SCIENCE AND ENGINEERING
(2022)
Article
Thermodynamics
Hui Wang, Bingzhu Lai, Zhiguo Qu, Pingwen Ming
Summary: A comprehensive model coupling the DSMC method with the finite difference method is proposed to investigate the heat transfer due to the impact of a moving rarefied hydrogen jet in low-pressure environments. The study analyzes the influences of different inlet pressures, jet apertures, and impact distances on the jet heat transfer intensity.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Thermodynamics
Charlotte Rudolph, Burak Atakan
Summary: A novel method for energy conversion in piston engines, pyrolysis of natural gas/hydrogen mixtures for energy storage, is investigated. The addition of hydrogen allows for increased yields of certain products but also reduces storage power and efficiency.
Article
Engineering, Chemical
Leila Dehdari, Iris Burgers, Penny Xiao, Kevin Gang Li, Ranjeet Singh, Paul A. Webley
Summary: The increasing global attention towards hydrogen as a green energy carrier is primarily due to environmental concerns related to global warming. The goal of this study was to produce high purity hydrogen from a mixture of hydrogen/natural gas using a bespoke pressure swing adsorption (PSA) cycle, achieving high purity hydrogen product (>99%) with high recovery (>85%) in the 30 bar feed stream.Comparative analysis indicated that the PSA system is competitive, even at a low hydrogen recovery of 40%, particularly when built at a pressure reduction station.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Chemistry, Physical
Hao Li, Xuewen Cao, Huimin Du, Lin Teng, Yanbo Shao, Jiang Bian
Summary: This paper establishes a numerical model to study the leakage and diffusion of hydrogen blended natural gas in a closed container. The results show that the flammable area with high hydrogen ratios has a longer risk duration, while the flammable area with low hydrogen ratios is relatively safer. The difference in diffusion rates between methane and hydrogen leads to faster diffusion of hydrogen to the middle and lower part of the enclosed container.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Thermodynamics
Di Fan, Jing Gong, Shengnan Zhang, Guoyun Shi, Qi Kang, Yaqi Xiao, Changchun Wu
Summary: The transient composition tracking method developed for natural gas pipe networks uses control volume and one-dimensional unsteady heat transfer models for simulation, enables real-time prediction of gas composition and consideration of its influence on property parameters. The method shows reliability and accuracy in case studies, but caution should be taken regarding the impact of injecting LNG/H-2.
Article
Engineering, Multidisciplinary
Xiyu Yang, Xiaoyan Wang, Quan Dong, Daijun Wei, Tanqing Zhou
Summary: This paper presents an innovative measurement method for a two-phase fuel transient flow rate in the same space-time dimension. Through jet momentum measurement and the design of a spray filter, the method enables spatial extraction of the target jet. With the optimized jet baffle structure, the quality of the test signal is greatly improved. Compared with traditional methods, this method has higher precision in measuring the shape of gas injection rate and recognizing the beginning and ending moments of gas injection. It can also be used to study the coupling effect of two-phase fuel injection and the influence of ambient pressure on injection performance.
Article
Chemistry, Physical
Iris Burgers, Leila Dehdari, Penny Xiao, Kevin Gang Li, Earl Goetheer, Paul Webley
Summary: This study proposes a pressure swing adsorption system for separating hydrogen from natural gas and evaluates the economic feasibility of supplying hydrogen at a refuelling station using this system. The findings suggest that hydrogen supplied by a pressure swing adsorption system is economically viable. Additionally, the study compares the hydrogen prices of two other supply methods, on-site electrolysis and tube-trailer transportation, and finds that they are relatively higher.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Engineering, Multidisciplinary
Xiyu Yang, Quan Dong, Hongjie Zhao
Summary: This paper presents an innovative measurement method to study the injection characteristics of a multi-point injection (MPI) system for natural gas engines. By measuring the change of gas pressure in the measurement chamber, the gas injection rate for different nozzle structures can be obtained. The study shows that the injection moment hysteresis and the injection duration vary with the injection pressure and energizing time. The results also indicate that the open-hole injection tube structure has a longer injection duration compared to the straight-through injection tube structure due to the inability to directly use the axial momentum of the gas flow.
Article
Energy & Fuels
Bonchan Koo
Summary: This paper presents a novel implicit method of characteristics (MOC) utilizing pressure-referenced characteristic line correction that ensures the efficiency and reliability of transient flow analyses for natural gas pipelines. The proposed method coordinates the characteristic line and corrects it using pressure gradients to enhance the computational efficiency and fidelity of the system.
JOURNAL OF NATURAL GAS SCIENCE AND ENGINEERING
(2022)
Article
Chemistry, Physical
Jingxuan Xu, Wensheng Lin
Summary: In this study, a new approach was proposed to produce liquid hydrogen and LNG from industrial by-products containing hydrogen and methane. Different separation-liquefaction processes were optimized to achieve high purity products and energy integration, with the specific energy consumption within a reasonable range. The results suggest the necessity of recovering cold energy of boil-off gas and recommend the use of an open loop system with nitrogen precooling.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
