Article
Chemistry, Physical
Patrick Rorimpandey, Ho Lung Yip, Ales Srna, Guanxiong Zhai, Armin Wehrfritz, Sanghoon Kook, Evatt R. Hawkes, Qing Nian Chan
Summary: This study investigates the ignition and combustion characteristics of diesel pilot and hydrogen jets under simulated compression-ignition engine conditions. The results show that the injection sequence and timing between injections significantly affect the combustion process. Igniting the hydrogen jet before the diesel pilot leads to better combustion performance, while delaying the ignition of the hydrogen jet reduces its combustion efficiency.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Energy & Fuels
Rafig Babayev, Arne Andersson, Albert Serra Dalmau, Hong G. Im, Bengt Johansson
Summary: Research shows that the non-premixed compression-ignition neat H-2 engine can achieve comparable or higher brake thermal efficiency than diesel, with 5-10% of total useful work contributed by H-2 injections at TDC. Additionally, H-2 fuel-air mixing in the free-jet phase is significantly higher due to hydrogen's gaseous state, low density, high injection velocity, and transient vortices, but the H-2 jet momentum is lower than diesel.
Article
Chemistry, Physical
Rafig Babayev, Arne Andersson, Albert Serra Dalmau, Hong G. Im, Bengt Johansson
Summary: This computational study evaluates the characteristics of H-2 direct-injection compression-ignition non-premixed combustion concept, focusing on hydrogen's unique features and the need to rethink optimization strategies for CI engines when using H-2 as fuel. The research contributes to the future development of DICI H-2 combustion engines by providing detailed characterization of the combustion cycle and highlighting key differences between CI non-premixed H-2 and diesel combustion.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Energy & Fuels
Jingrui Li, Haifeng Liu, Xinlei Liu, Ying Ye, Hu Wang, Mingfa Yao
Summary: The study investigates the detailed combustion kinetics of a high-pressure direct injection natural gas marine engine, observing that an earlier NG start of injection timing results in a higher heat release rate with limited impact on the main representative exothermic reactions and dominant formation reactions of CH2O and OH.
Article
Energy & Fuels
Zhenxian Zhang, Wuqiang Long, Pengbo Dong, Hua Tian, Jiangping Tian, Bo Li, Yang Wang
Summary: In this study, the Ammonia/Diesel dual direct injection mode of a two-stroke low speed engine was evaluated. It was found that the injection timing of diesel can regulate the engine combustion phase, improving the combustion efficiency and indicated thermal efficiency of ammonia. Furthermore, by optimizing the injection timings of diesel and ammonia, the fuel type NOx emission produced by ammonia combustion can be reduced.
Article
Thermodynamics
Jose Antonio Velez Godino, Miguel Torres Garcia, Francisco Jose Jimenez-Espadafor Aguilar
Summary: Experimental study on a compression ignition engine using late direct injection of rapeseed biodiesel fuel blends shows a significant reduction in nitrogen oxides emissions without compromising performance, indicating an advanced combustion mode between traditional compression ignition engines and homogeneous charge compression ignition combustion mode.
Article
Chemistry, Physical
Prem Kumar Chaurasiya, Upendra Rajak, Ibham Veza, Tikendra Nath Verma, Umit Agbulut
Summary: In this research, the combustion performance of diesel fuel, diethyl ether, n-butanol, and spirulina microalgae was investigated by adding 5% hydrogen. The results showed that the blend of 5% hydrogen with 95% diethyl ether consistently had the highest specific fuel consumption with advancing injection timings. The addition of 5% hydrogen into 95% n-butanol resulted in a relatively stable brake thermal efficiency for all injection timings. The use of n-butanol consistently produced the lowest emissions of CO2, smoke, NOX, and particulate matter throughout the entire injection timings.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Energy & Fuels
Yikang Cai, Ming Jia, Guangfu Xu, Yaopeng Li, Tianyou Wang
Summary: The study compared the optimization of DI2 and RCCI at mid load, finding that DI2 can achieve lower NOx emissions and near-zero soot emissions while maintaining high fuel economy, but usually results in higher emissions of NOx, soot, and CO2 compared to RCCI. In the optimal DI2 cases, very advanced n-butanol injection timing, high n-butanol energy fraction, and early diesel injection timing were adopted.
Article
Green & Sustainable Science & Technology
Josimar Souza Rosa, Giovani Dambros Telli, Carlos Roberto Altafini, Paulo Roberto Wander, Luiz Alberto Oliveira Rocha
Summary: The study explores the feasibility of using ethanol as a partial fuel in a generator set by analyzing technical, environmental, and economic aspects. Tests conducted on a diesel single-cylinder engine with an added PFI system for ethanol supply showed that ethanol effectively increased ignition delay and reduced combustion duration, though without improving efficiency or reducing fuel consumption. Ethanol also led to decreased CO and NOx emissions, but resulted in a slight increase in operational costs compared to using only diesel fuel.
JOURNAL OF CLEANER PRODUCTION
(2021)
Article
Chemistry, Multidisciplinary
Xuejiao Dai, Aqian Li, Zhaolei Zheng
Summary: In this study, numerical simulation is used to investigate the effects of different water injection pressures on knock combustion of turbocharged direct injection gasoline engines. The results show that direct water injection significantly reduces knock intensity, with complete suppression observed at water injection pressures above 40 bar. The study also explores the impacts of water injection pressure on water evaporation, in-cylinder combustion, and the knocking mechanism.
Article
Energy & Fuels
Hechun Wang, Binbin Wang, Chuanlei Yang, Deng Hu, Baoyin Duan, Yinyan Wang
Summary: This paper studies the dual injection strategy of a diesel ignition ammonia/hydrogen mixed fuel engine through simulation, selecting the optimal combination of dual injection timing to improve combustion and emission performance. The results show that with delayed fuel injection timing, engine power and economy decline, while HC, soot, CO, and N2O emissions increase and NOx emissions decrease. After using ammonia/hydrogen mixed fuel, ammonia and hydrogen escape are low, and the emission of HC, soot, and CO is also low. The best injection timing combination is D698/A/H698, which has the best power and economic performance. N2O emissions are low, but NOx emissions are relatively high. The research results can promote the development of ammonia fuel and provide theoretical guidance for its practical application. Evaluation: 9/10.
Article
Energy & Fuels
Mohammad Taghi Zarrinkolah, Vahid Hosseini
Summary: Alternative combustion mode and change of spray geometry have the potential to reduce methane slip in a dual fuel diesel-natural gas internal combustion engine. Two reactivity controlled compression ignition (RCCI) modes show better results compared to conventional diesel methane dual-fuel combustion. The angle of diesel spray also affects methane slip, with spray towards the squish area reducing slip.
Article
Thermodynamics
Rafig Babayev, Arne Andersson, Albert Serra Dalmau, Hong G. Im, Bengt Johansson
Summary: The study demonstrates that optimizing piston bowl designs and injector parameters can effectively maximize free-jet mixing, reduce wall heat transfer, and improve indicated efficiency. However, at low excess air ratios, elevated incomplete combustion losses may occur. Ultimately, noise emissions from optimized DICI H-2 combustion are shown to be comparable to conventional diesel engines.
INTERNATIONAL JOURNAL OF ENGINE RESEARCH
(2022)
Article
Chemistry, Physical
G. Maio, A. Boberic, L. Giarracca, D. Aubagnac-Karkar, O. Colin, F. Duffour, K. Deppenkemper, L. Virnich, S. Pischinger
Summary: This paper presents the optimization of the combustion process in the H-2 internal combustion engine through experimental and numerical investigations. The effects of direct injection and port fuel injection configurations on performance are discussed. Experimental results show that the port fuel injection configuration provides advantages in terms of efficiency and emissions, but at the expense of volumetric efficiency. The proposed numerical model successfully simulates different engine operating conditions.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Energy & Fuels
Avinash Kumar Agarwal, Akhilendra Pratap Singh, Vikram Kumar
Summary: In this experimental investigation, the effects of different pilot injection techniques on reactivity-controlled compression ignition (RCCI) combustion were explored. The study found that both advanced and retarded start of diesel injection (SoIdiesel) timings resulted in combustion noise and misfire. The use of pilot injection was suitable for the RCCI mode, especially at lower premixed ratios (rp) of methanol. Optimizing the rp of methanol and adopting a suitable injection strategy can significantly improve the combustion, performance, and emissions characteristics of the RCCI mode.
Article
Chemistry, Physical
Ugochukwu Ngwaka, Andrew Smallbone, Boru Jia, Christopher Lawrence, Ben Towell, Sumit Roy, K. Shivaprasad, Anthony Paul Roskilly
Summary: The experimental results show that equivalence ratio and engine speed affect engine operation characteristics, and it is important to avoid unwanted disturbance to the electric generator operation. The four-stroke cycle mode has a higher indicated thermal efficiency compared to the two-stroke cycle mode.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Thermodynamics
Huihua Feng, Zhiyuan Zhang, Boru Jia, Zhengxing Zuo, Andrew Smallbone, Anthony Paul Roskilly
Summary: The FPEG is a new energy conversion device that converts the chemical energy of fossil fuels into electric energy and is suitable for range extenders in electric vehicles. Research on the optimal compression ratio of FPEG during cold start shows that the target compression ratio is crucial while the operating frequency has minimal impact on system performance.
APPLIED THERMAL ENGINEERING
(2021)
Review
Energy & Fuels
Yidong Fang, Yiji Lu, Anthony Paul Roskilly, Xiaoli Yu
Summary: The article describes the application of emission free compressed air powered energy system in vehicular transportation, including technological development, design of compressed-air powered powertrain, and advantages and limitations of pneumatic hybrid technologies. It discusses the opportunities and challenges for compressed-air technology in transportation applications.
ENERGY STRATEGY REVIEWS
(2021)
Article
Energy & Fuels
Zhi Li, Yiji Lu, Rui Huang, Jinwei Chang, Xiaonan Yu, Ruicheng Jiang, Xiaoli Yu, Anthony Paul Roskilly
Summary: This article presents a comprehensive review of latent thermal energy storage technology, focusing on medium-high temperature phase change materials. The key points include insights into phase change materials, design of heat exchangers, and applications in various thermal sources such as solar energy and waste heat.
Article
Thermodynamics
Zhiyuan Zhang, Huihua Feng, Boru Jia, Zhengxing Zuo, Andrew Smallbone, Anthony Paul Roskilly
Summary: The study investigates the impact of stroke-to-bore ratio on the operation and performance of a free piston engine generator, finding that S/B ratio and compression ratio significantly affect parameters such as operating frequency, indicated power, and thermal efficiency, providing important design guidance for improving engine performance.
APPLIED THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Ugochukwu Ngwaka, Dawei Wu, Julian Happian-Smith, Boru Jia, Andrew Smallbone, Chidiebere Diyoke, Anthony Paul Roskilly
Summary: The paper presents a novel semi-closed-loop Linear Joule Engine Generator (LJEG) using argon as the major working fluid and oxy-hydrogen combustion. Through experiments and model analysis, the advantages of the new design over using air as the working fluid are demonstrated.
Article
Thermodynamics
Ziwen Cheng, Boru Jia, Zhenfang Xin, Huihua Feng, Zhengxing Zuo, Andrew Smallbone, Anthony Paul Roskilly
Summary: The study investigated the effects of variable-scavenging-timing technology on the performance of free-piston engine generators, showing that this technology can improve scavenging quality and performance.
APPLIED THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Matthew Hodgson, Sumit Roy, Anthony Paul Roskilly, Andrew Smallbone
Summary: This study investigates the performance and efficiency of closed-loop oxy-hydrogen Brayton power cycles through numerical modelling and simulation. It is found that by adding components such as an intercooler, reheater and regenerator, the efficiency of the cycle can be significantly increased. The hydrogen-helium cycle is more efficient, but also the most expensive to operate.
ENERGY CONVERSION AND MANAGEMENT
(2021)
Article
Economics
Renaldi Renaldi, Richard Hall, Tooraj Jamasb, Anthony P. Roskilly
Summary: This study presents the experience curves of low-carbon domestic heating technologies in the UK from 2010 to 2019, highlighting their deployment as a key action for decarbonizing the heating sector. The findings show that the experience rates of these technologies are significantly lower than those reported in the literature, providing valuable insights for energy economics models and policymakers. The study also suggests that gas boilers may have reached a floor price, prompting the need for further deployment programs.
Article
Green & Sustainable Science & Technology
Max Patel, Sumit Roy, Anthony Paul Roskilly, Andrew Smallbone
Summary: This research introduces a novel method called "Hydrogen Interconnector System" (HIS) for long-distance electrical energy transportation. It converts stranded renewable energy into hydrogen and transports it via pipelines to the demand center, where it is reconverted to electricity. The study shows that the HIS is competitive with High Voltage Direct Current (HVDC) systems in terms of economic and technological indicators, and it also has lower investment costs in certain scenarios.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Energy & Fuels
Max Albert, Zhiwei Ma, Huashan Bao, Anthony Paul Roskilly
Summary: Pumped Thermal Energy Storage (PTES) technology offers multidimensional advantages, with findings indicating that longer and thinner thermal storage tanks can increase system efficiency. Operating with larger 'temperature ratio' segmentation can also improve round-trip efficiency, while the duration of the high power region and steepness of the power front significantly impact power output.
Article
Thermodynamics
A. Giampieri, Z. Ma, J. Ling-Chin, A. P. Roskilly, A. J. Smallbone
Summary: The study reviews the role of HVAC systems in airborne viral transmission and estimates the energy penalty associated with their adoption. Liquid desiccant technology is proposed as a solution to improve indoor air quality and reduce the infectivity of pathogens. The study concludes that liquid desiccant technology could be beneficial in buildings or enclosed spaces where humidity control is needed or during virus outbreaks.
Article
Thermodynamics
Zhiyuan Zhang, Huihua Feng, Boru Jia, Zhengxing Zuo, Xiaodong Yan, Andrew Smallbone, Anthony Paul Roskilly
Summary: Stable combustion in dual-cylinder free-piston engine generators is a challenge due to potential variations in both cycles and between cylinders. The system shows anti-interference properties but is sensitive to external conditions and operating parameters. Simulation results indicate that the system can quickly return to a stable state after single combustion variations.
Article
Energy & Fuels
L. Jiang, Y. C. Lin, W. Liu, Z. W. Ma, R. Q. Wang, X. J. Zhang, A. P. Roskilly
Summary: Sorption thermal energy storage is a promising method for reducing building heating energy consumption. MgCl2·6H2O shows high energy storage density and good performance in open sorption thermal energy storage systems.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2022)
Article
Green & Sustainable Science & Technology
Annie Chimphango, Richard Kingsley Padi, Anthony Paul Roskilly
Summary: This study evaluates the economic and environmental performance of cassava waste bioenergy production in seven African countries. The findings suggest that utilizing cassava stems and cassava starch wastewater for bioenergy generation is feasible and has positive impacts on both the economy and the environment.
SUSTAINABLE PRODUCTION AND CONSUMPTION
(2022)
