Article
Energy & Fuels
R. Rabello de Castro, P. Brequigny, J. P. Dufitumukiza, C. Mounaim-Rousselle
Summary: Syngas, a gaseous biofuel, requires operation mode adaptation when used for stationary electricity generation in Internal Combustion engines. Research indicates that combustion parameters of different syngas compositions from various gasifiers affect flame speeds, with Updraft and Downdraft compositions showing higher speeds. Kinetic modeling results show good overall agreement with experimental data, with CRECK mechanism deviating by only 5-10%.
Article
Thermodynamics
Haoyang Li, Jinyuan Hao, Zhiming Du, Tianwei Zhang
Summary: In this study, the laminar flame speed (S-L) of pyrolysis gas from red pine wood was investigated. The results showed that the laminar flame speed of the gas increased with the increase of pyrolysis temperature. The effect of hydrocarbon gases on the laminar flame speed was linear in a certain concentration range, while the effect of H-2, CO, and CO2 followed a quadratic polynomial distribution.
CASE STUDIES IN THERMAL ENGINEERING
(2022)
Article
Thermodynamics
Wenkai Shen, Chang Xing, Haiqing Liu, Li Liu, Qiming Hu, Guohua Wu, Yujia Yang, Shaohua Wu, Penghua Qiu
Summary: This research combines EGR with an adjustable fuel feeding combustor to assess the part-load performance of a 300 kW MGT and the flame spatio-temporal characteristics. The results show that EGR can effectively reduce emissions and improve fuel flexibility.
Article
Engineering, Industrial
Pascale Vacca, Eulalia Planas, Christian Mata, Juan Antonio Munoz, Frederic Heymes, Elsa Pastor
Summary: The combustion of artificial fuels at Wildland-Urban Interface (WUI) homeowner scale is a significant contributor to fire spread through a property, posing major safety issues at the community level. Real-scale burning tests were conducted to gather quantitative data on these fuels and evaluate vulnerabilities of WUI properties through Performance-Based Design methodologies, with results indicating that certain fuel packs are more hazardous than others.
Article
Thermodynamics
Tong Xu, Peng Lei
Summary: This paper experimentally studied the temperature profile and flame height variation of a diesel-wetted wood powder fire. The study found that the combustion process can be divided into three stages and that the heat release rate of this kind of fire is lower than that of a pool fire with the same burner size. The flame height also decreases as the fuel feed rate decreases.
CASE STUDIES IN THERMAL ENGINEERING
(2022)
Article
Chemistry, Physical
Debojit Sharma, Anand Shankar Singh, Radi Alsulami, Bok Jik Lee, S. K. Dash, V. Mahendra Reddy
Summary: The combustion and ignition characteristics of three fuels with different reactivities have been investigated using a simplified chemical kinetic model. Blending hydrogen with hydrocarbon fuels improves flame propagation, reduces emissions, and increases engine combustion performance. An extensive analysis of different test mixtures under various conditions was conducted to analyze ignition delay time, laminar flame speed, flame temperature, and heat release rate characteristics.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Energy & Fuels
Yu Wang, Jianfeng Pan, Junfeng Wang, Qingbo Lu, Yi Zhang, Evans K. Quaye
Summary: The FREI dynamics of methane/oxygen mixture were experimentally observed in a micro quartz tube combustor. A 2-D model successfully predicted the propagation features of the FREI flame, which were in agreement with the experimental results. Four stages of flame front propagation were revealed based on simulations: accelerating stage, decelerating stage, reverse propagating stage, and weak reaction stage. Further analysis on radical and heat release rate (HRR) confirmed that the regeneration of CH4 behind the flame front and the reducing consumption of the overall amount of methane were the main factors for flame deacceleration and eventually extinction. After extinction, methane consumption tended to occur along the combustor wall due to the high wall temperature.
Article
Thermodynamics
V. Macian, F. J. Salvador, J. De la Morena, V. Pagano
Summary: The combustion process inside a stratified pre-chamber ignition system is analyzed using a zero-dimensional model and a thermodynamic model to evaluate flame propagation speed and factors influencing it. Results show consistent flame speed values when maintaining equivalence ratio in the pre-chamber, while lean operation leads to significant deterioration in speed.
COMBUSTION AND FLAME
(2021)
Article
Thermodynamics
Luming Fan, Bo Tian, Cheng Tung Chong, Mohammad Nazri Mohd Jaafar, Kenji Tanno, Dante McGrath, Pedro M. de Oliveira, Bernd Rogg, Simone Hochgreb
Summary: In this study, the impact of fuel droplets on stretched laminar flame speeds was investigated by adding small acetone droplets to methane/air mixtures. It was found that the presence of droplets altered the relationship between flame speed and strain rate, especially under rich conditions. Unlike fully vaporized flames, a two-stage reaction flame structure was observed with droplets, indicating a change in flame behavior.
COMBUSTION AND FLAME
(2021)
Article
Thermodynamics
Andrea Nobili, Luna Pratali Maffei, Matteo Pelucchi, Marco Mehl, Alessio Frassoldati, Andrea Comandini, Nabiha Chaumeix
Summary: This study provides the first measurements of laminar flame speed profiles of AMN/air mixtures, paving the way for the kinetic study of AMN combustion chemistry at high temperatures.
PROCEEDINGS OF THE COMBUSTION INSTITUTE
(2023)
Article
Thermodynamics
Shuai Yan, Yan Gong, Zhengqiao Duan, Qinghua Guo, Guangsuo Yu
Summary: The correlation between heat release rate and OH*, CH* chemiluminescence in methane inverse diffusion flame is explored. It is found that the flame heat release rate is mainly related to the formation and consumption of several species. The gradient of ground state OH concentration and the distribution of CH* and OH* are consistent with the heat release rate distribution.
Article
Thermodynamics
Carson Chu, Yasaman Amidpour, Nick A. Eaves, Murray J. Thomson
Summary: The study found that elevating reactant temperatures has a positive effect on soot formation in a laminar coflow ethylene flame, mainly due to enhanced soot surface growth. Additionally, it was revealed that PAH adsorption becomes more important at high temperatures, contributing up to 70% of the mass of soot formation.
COMBUSTION AND FLAME
(2021)
Article
Energy & Fuels
Baisheng Liao, Xiaoyu Ju, Dimeng Lai, Lizhong Yang
Summary: This study experimentally investigated the ignition and combustion behavior of PET laminated photovoltaic panels using the Fire Propagation Apparatus. The results showed that the ignition time was sensitive to the change of external heat flow, and increased ventilation significantly shortened the ignition time at lower external heat flows. The heat release rate and combustion equivalent ratio were positively correlated with the external radiant heat flow and ventilation. The total heat release was mainly influenced by the external radiant heat flow, but ventilation played a significant role, especially at low external heat flows.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2023)
Article
Energy & Fuels
Zhenhua Tang, Kun Zhao, Zhirong Wang, Jizhe Wang, Yi Pan
Summary: This study focuses on the burning behaviors of horizontal hydrogen jet fires under the action of a water curtain system. The experimental results show that the shape of the hydrogen jet flame expanded on the water curtain is elliptical at different conditions. A new dimensionless heat release rate is proposed to estimate the flame extension length.
Article
Chemistry, Physical
Hui-Sheng Peng, Bei-Jing Zhong
Summary: Experiments were conducted to determine the effects of composition distribution on the laminar flame speeds of various pyrolysis products. It was found that the compositions of pyrolysis gases were similar, while the compositions of pyrolysis liquids varied significantly under different cracking conditions. The laminar flame speeds of different pyrolysis products showed significant differences, which were related to both the pyrolysis gas content and the properties of the pyrolysis liquids.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Materials Science, Multidisciplinary
Huiying Tian, Kai Wang, Ziyi Shui, Muhammad Ali Raza, Hang Xiao, Meidan Que, Liangliang Zhu, Xi Chen
Summary: Metal phthalocyanines molecular catalysts demonstrate unique ability in CO2 electrochemical reduction reaction (CO2ERR) due to their well-defined macrocycle structure. By introducing different substituent functional groups on the phthalocyanine ring of cobalt phthalocyanine, the relationship between molecular structure optimization and CO2ERR activity was studied. An optimal nitro-substituted cobalt phthalocyanine catalyst can achieve high selectivity of 94% in converting CO2 to CO, with a current density of 12.6 mA cm(-2) at -0.877 V vs. RHE. Insights gained from this study on designing and optimizing molecular catalysts contribute to lower energy and cost-effective CO2ERR.
Article
Chemistry, Multidisciplinary
Kai Wu, Ting Zhu, Liangliang Zhu, Yu Sun, Kai Chen, Jiaorui Chen, Haozhi Yuan, Yaqiang Wang, Jinyu Zhang, Gang Liu, Xi Chen, Jun Sun
Summary: In this study, we report three reversible mechanochromic phenomena in simple material systems by harnessing mechano-responsive wrinkling dynamics. The results demonstrate the potential applications of these materials in smart displays, stretchable strain sensors, and antipeeping/anticounterfeiting devices.
Article
Multidisciplinary Sciences
Nandan H. Shetty, Robert M. Elliott, Mark Wang, Matthew Palmer, Patricia J. Culligan
Summary: This study compares the hydrological performance of green roofs with native vegetation and drought-tolerant succulents in the New York City area. The results show that irrigated green roofs with native vegetation have better stormwater retention and higher evapotranspiration.
Article
Engineering, Chemical
Feng Li, Yifan Zhang, Shiqiang Zheng, Kai Wang, Jia Ni, Liangliang Zhu, Xi Chen
Summary: The adsorption performance of a resin-based ion-exchange membrane loaded with CO32- was investigated in different CO2 concentrations and relative humidity. The study indicated that the moisture sensitivity of the adsorption capacity decreased with the initial CO2 concentration.
ASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING
(2022)
Article
Engineering, Environmental
Xueyan Sun, Liangliang Zhu, Wei Zhao, Feng Li, Xi Chen
Summary: In this study, a chemical looping scheme was developed to efficiently reduce impure CO2 containing O-2 impurities into high value-added substances. The synergistic effect of Ni and Fe played a key role in achieving high conversion and yield. This work presents a promising approach for direct utilization of impure CO2 and achieving carbon-neutral economic development.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Materials Science, Multidisciplinary
Sile Yu, Ziyi Shui, Chenghua Wang, Yuan Lei, Yilun Liu, Wei Zhao, Xi Chen
Summary: A series of La0.8Sr0.2FeO3-based perovskite catalysts have been created by sol-gel method, which can substitute expensive precious metal catalysts and exhibit higher ORR and OER performance.
JOURNAL OF MATERIALS SCIENCE
(2022)
Article
Construction & Building Technology
Lixi Liu, Yilun Liu, Xiaogeng Tian, Xi Chen
Summary: This study demonstrates that carbonation curing using flue gas can lead to higher CO2 uptake and compressive strength compared to pure CO2 curing. The rate of flue gas carbonation is slower at the beginning, but the CO2 uptake and compressive strength are higher than pure CO2 after 12 hours of carbonation. Furthermore, by properly combining carbonation and hydration curing, the 28-day strength of flue gas carbonated specimens can exceed that of hydration specimens.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Ziyi Shui, Yuzhi Chen, Wei Zhao, Xi Chen
Summary: There is a urgent need for high-performance flexible batteries in emerging fields, such as flexible electronics, wearable sensors, and implantable medical devices. However, the safety and stability issues of traditional organic liquid-based electrolytes limit their use in flexible batteries. This study explores gel electrolytes with superior ionic conductivity and safety to solve this problem. Two types of gel polymer electrolyte membranes are created and integrated into flexible aluminum-air batteries, and their discharge properties under different bending states are discussed. The results show that the gel electrolytes have high ionic conductivity and can meet the flexibility requirements, although there might be a slight loss of power density under bending conditions. Overall, a flexible aluminum-air battery based on PVDF-[C(4)mpyr]Cl is suitable for high-power applications with low bending angles, while a PVDF-[BMIM]Cl-based battery is favored for low-power devices with high flexibility requirements.
Article
Chemistry, Physical
Muhammad Ali Raza, Huiying Tian, Ziyi Shui, Liangliang Zhu, Meidan Que, Xi Chen
Summary: The development of high-efficient photocatalysts for CO2 reduction is crucial for addressing global energy and environmental challenges. This study presents a 2D/2D hierarchical heterostructure of NiFeV layered double hydroxide (LDH) nanosheets and g-C3N4, which significantly enhanced the photocatalytic performance. The weight ratio of g-C3N4 to NiFeV-LDH had a significant impact on the catalytic activity, with the highest yields of CH4 and CO generated when the ratio was 15%.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2022)
Article
Materials Science, Multidisciplinary
Ziyi Shui, Huiying Tian, Sile Yu, Hang Xiao, Wei Zhao, Xi Chen
Summary: This study demonstrates the creation of Mn-based perovskite nanoparticles with excellent bifunctional oxygen electrocatalysis through precise control of their electronic structures. The results show promising potential for rechargeable Zn-air batteries.
SCIENCE CHINA-MATERIALS
(2023)
Article
Chemistry, Physical
Ziyi Shui, Huiying Tian, Muhammad Ali Raza, Liangliang Zhu, Wei Zhao, Xi Chen
Summary: Rechargeable Zn-air batteries are considered promising energy storage devices due to their high energy and power density, safety, and cost-effectiveness. However, the sluggish kinetics of the oxygen reaction during discharge and charge processes have hindered their practical application. In this study, LSFMO nanoparticles synthesized with a modified coprecipitation method exhibited high intrinsic activities. Furthermore, the synergic covalent coupling between N/S dual-doped reduced graphene and LSFMO significantly improved the oxygen reduction and evolution reaction capabilities of the LSFMO@NS-RGO hybrid material. The excellent results demonstrated that LSFMO@NS-RGO represents a new class of promising bifunctional catalysts for rechargeable Zn-air batteries.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Multidisciplinary
Chenghua Wang, Huiyu Huang, Xueyan Sun, Xiaobin Deng, Yuan Lei, Wenbing Hao, Yilun Liu, Xi Chen, Wei Zhao
Summary: In this work, a new electrolyte design using a polydentate ligand to stabilize the zinc ion and triethanolamine (TEA) as an anionic surfactant is proposed, which greatly suppresses the passivation film formation and improves the efficiency of the zinc anode. The experimental results show that the specific capacity of the battery with the effect of TEA is significantly improved compared to the traditional electrolyte, and the zinc anode self-corrosion is mitigated. The density functional theory calculations confirm the existence and structure of the new complex in electrolytes.
Article
Green & Sustainable Science & Technology
H. Tian, L. Zhu, J. Ni, T. Wei, P. Wang, H. Xiao, X. Chen
Summary: Growing evidence suggests that even a low CO2 concentration of 1000 ppm can pose direct health risks to humans, which is often exceeded in many indoor environments. To address this issue, we developed a CO2 purification module using a moisture swing sorbent and integrated it with existing air conditioning units. The sorbent can spontaneously bind and release CO2 from the air, depending on the moisture level, making it an ideal solution for indoor carbon capture. Tests in simulated indoor environments and an actual office demonstrated the effectiveness of the purification module in maintaining healthy CO2 levels. This decentralized carbon capture facility has the potential to contribute to negative emissions and mitigate the global warming and climate change crisis.
MATERIALS TODAY SUSTAINABILITY
(2023)
Article
Chemistry, Physical
Huiying Tian, Ziyi Shui, Liangliang Zhu, Xi Chen
Summary: Fe/Ni-N-C materials were successfully constructed and evaluated in a typical H cell, showing a highest CO Faradaic efficiency of 92.9% and a largest turnover frequency of 10.77 x 103 h-1 at - 0.677 V vs. RHE. When transferred to a larger-scale continuous flow cell, Fe/Ni-N-C exhibited higher current density and FECO with robust durability, preserving over 89% of FECO after 40 hours of electrolysis. The synergetic effects of binary metals effectively enhanced the charge transfer rate and provided favorable kinetics. Furthermore, an aqueous Zn-CO2 battery assembled with Fe/Ni-N-C as the cathode demonstrated excellent charge-discharge cycle stability, serving as the electricity supply for ECR.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Proceedings Paper
Computer Science, Theory & Methods
Wei Fan, Kevin A. Kam, Haokai Zhao, Patricia J. Culligan, Ioannis Kymissis
Summary: An optical absorbance-based sensor has been developed to measure the concentration of essential nutrients in urban soil. The sensor is capable of operating in different ambient light settings and has shown that street-tree pits contain higher levels of nutrients compared to park spaces. This new technology will contribute to better monitoring of soil nutrient conditions and the promotion of healthy green spaces in urban environments.
2022 18TH INTERNATIONAL CONFERENCE ON INTELLIGENT ENVIRONMENTS (IE)
(2022)
