Hasil untuk "Fuel"

L. Lynd

S. Haile, D. Boysen, C. Chisholm et al.

Shabbir Ahmed, M. Krumpelt

C. Rice, S. Ha, R. Masel et al.

C. Dyer

Cheng Wang, Mahesh Waje, Xin Wang et al.

J. Roziere, Deborah J. Jones

G. Tzeng, Cheng-Wei Lin, S. Opricovic

N. Brandon, S. Skinner, B. Steele

Akta Singh, Nayana Mukherjee, Jagannath Mondal et al.

Chemically fueled supramolecular systems can exhibit complex, time-dependent behaviors reminiscent of living matter when maintained far from equilibrium by continuous energy or fuel consumption. Here, we introduce a minimal reaction-diffusion model that captures the essential dynamics of a cooperative supramolecular polymerization network driven by monomer activation and deactivation. We show that a balance between autocatalytic growth and inhibitory decay sustains a nonequilibrium steady state in the model that undergoes a Hopf bifurcation, giving rise to autonomous oscillations. When spatial transport is introduced through diffusion, the system displays rich spatiotemporal phenomena, such as traveling wavefronts and transient polygonal patterns. Our results demonstrate that the interplay between reaction kinetics and diffusion can spontaneously generate self-organized, life-like dynamics in synthetic supramolecular polymer systems. This theoretical framework not only bridges molecular self-assembly and active matter dynamics but also provides design principles for creating adaptive, oscillatory, and self-patterning materials powered by chemical fuels.

Ali Murtaza Ansari, Liaquat Ali Memon, Mohamed Y.E. Selim et al.

Alcoholic fuels have lately been found to be a viable source of power for contemporary cars. Particles pose a major hazard to both human health and the biosphere. These days, strict pollution regulations make fuel and combustion system improvements insufficient. Lubricant use is another important element that contributes to the degradation of engine PM emissions, in addition to fuel. Understanding how lubricants impact the composition and properties of PM is essential for both reducing PM formation and maximizing PM oxidation. The effects of alcoholic fuels on engine performance and emissions have been the subject of numerous studies. There has been concern that this would result in more particulate matter being discharged with the exhaust, which would have a detrimental effect on the air quality. This study examines the size-distribution of uncontrolled particulate matter (PM) generated along with exhaust gases. PM exhaust emissions were examined with the engine running at a constant 1500 rpm and a constant load. 10% (G90E10) ethanol and 10% (G90nBn10) n-butanol were added to ethanol-gasoline and n-butanol-gasoline fuel mixtures in order to evaluate their engine characteristics and lubricating oil condition with those of pure gasoline. In order to determine the rate of deterioration, the characteristics of the lubricating oil were evaluated following 200 h of engine use, as advised by the manufacturer. A reciprocating test rig was used to obtain the trial results every 20 h. The wear metals lead (0.030, 0.029, and 0.023 PPM), cobalt (0.0062, 0.0046, and 0.0038 PPM), and cadmium (0.0033, 0.0032, and 0.0026 PPM) were measured for the lubrication oil examination. In general, N-butanol reduces pollutants, engine wear debris, and lubricating oil oxidation. Additionally shown are the variations in the viscosity of the lubricant oil before and after 200 h of use.

E. Kjeang, N. Djilali, D. Sinton

W. Cooke, C. Liousse, H. Cachier et al.

A. Weber, J. Newman

C. D. Rakopoulos, K. A. Antonopoulos, D. Rakopoulos et al.

V. Sajith, C. Sobhan, G. Peterson

This paper reports the results of experimental investigations on the influence of the addition of cerium oxide in the nanoparticle form on the major physicochemical properties and the performance of biodiesel. The physicochemical properties of the base fuel and the modified fuel formed by dispersing the catalyst nanoparticles by ultrasonic agitation are measured using ASTM standard test methods. The effects of the additive nanoparticles on the individual fuel properties, the engine performance, and emissions are studied, and the dosing level of the additive is optimized. Comparisons of the performance of the fuel with and without the additive are also presented. The flash point and the viscosity of biodiesel were found to increase with the inclusion of the cerium oxide nanoparticles. The emission levels of hydrocarbon and NOx are appreciably reduced with the addition of cerium oxide nanoparticles.

Erik Brücken, Peter Andersson, Mihaela Bezak et al.

Spent nuclear fuel imaging before disposal is of utmost importance before long term disposal in dedicated storage facilities. Passive Gamma Emission Tomography (PGET) is an approved method by the International Atomic Energy Agency. The present detection system is based on small CZT detectors behind a tungsten-based collimator consisting of a linear array of slits. Small scale CZT crystals limit the detection efficiency of high energetic gamma rays from the fuel rods, mainly the 662 keV emissions from Cs-137. In our study based on full Monte-Carlo simulations as well as on experiments, we explore the capabilities of large pixelated CZT detectors to be used for PGET. We will discuss the theoretical advantages and practical challenges of the larger crystals. We demonstrate that the larger crystals, depending on their orientation, will increase the detection efficiency by a factor of 7 to 13. Due to the pixelated sensor signal readout we also explore the possibility to employ Compton imaging to improve the information on the location of origin of gamma rays. In addition we explore the usefulness of commercial gamma-ray imagers for waste characterisation and decommissioning. In particular we report on the performance of the GeGI imager from PHDS Co and the H420 imager from H3D Inc in measuring nuclear waste drums at Svafo, Sweden.

Javier Ruiz-Pineda, Jaime Romero-Barrientos, Francisco Molina et al.

OpenMC is an open-source Monte Carlo code with increasing relevance in criticality safety and reactor physics applications. While its validation has covered a broad range of systems, its performance in spent nuclear fuel storage scenarios remains limited in the literature. This work benchmarks OpenMC against MCNP for eleven configurations based on the KBS-3 disposal concept, involving variations in geometry, fuel composition (fresh vs spent), and environmental conditions (e.g., air, argon, flooding scenarios). Effective multiplication factors (k-eff) and leakage fractions were evaluated for both codes. Results show strong agreement, with code-to-code k-eff differences below 0.8% in dry storage conditions, and consistent trends across all cases. Notably, OpenMC successfully captures inter-canister neutron interaction effects under periodic boundary conditions, demonstrating its applicability to dry storage configurations. This benchmark supports the extension of the validation domain of OpenMC toward SNF transport and disposal applications.

Yuxiang Xu, Wenjuan Yu, Yuqian Wan et al.

This study addresses critical challenges in managing the transportation of spent nuclear fuel, including inadequate data transparency, stringent confidentiality requirements, and a lack of trust among collaborating parties, issues prevalent in traditional centralized management systems. Given the high risks involved, balancing data confidentiality with regulatory transparency is imperative. To overcome these limitations, a prototype system integrating blockchain technology and the Internet of Things (IoT) is proposed, featuring a multi-tiered consortium chain architecture. This system utilizes IoT sensors for real-time data collection, which is immutably recorded on the blockchain, while a hierarchical data structure (operational, supervisory, and public layers) manages access for diverse stakeholders. The results demonstrate that this approach significantly enhances data immutability, enables real-time multi-sensor data integration, improves decentralized transparency, and increases resilience compared to traditional systems. Ultimately, this blockchain-IoT framework improves the safety, transparency, and efficiency of spent fuel transportation, effectively resolving the conflict between confidentiality and transparency in nuclear data management and offering significant practical implications.

A. Quadling

This paper represents one half of a set of two, covering the TECHNOLOGY presentations at the Fusion Energy Conference (FEC), held in London, UK, in October 2023. Dominant themes include the use of computing codes to pre-determine machine performance in fusion device design, the impetus that ITER and DEMO are providing for component fabrication innovation, and a growing global focus on blanket materials and fuel retention mechanisms. New themes include power plant costing and the control of activated corrosion products. Stellarator technology is noted, but this is not yet a strong innovation theme at FEC. The latest fusion material science considers operating conditions in power plant service, especially the impact of fuel cycle and superconducting magnet fields; fuel cycle technologies consider electrical coupling and the need for insulating components to control the magnetohydrodynamic response. Optimising correction coils and the thickness of Toroidal Field components to withstand loads is becoming increasing critical in next-step machine design. The latter increasingly utilises integrated frameworks for high-fidelity modelling. Whether coupling armour, blanket and shielding or dose rate fields with geometry, these platforms require high-performance computing. With respect to power plant programmes, the DEMO design continues to assume pulsed operation; JA DEMO, with or without neutral beam injection, sees the electron cyclotron scenario enabling 2 h of pulsed operation at 80 MW of external heating and current drive power. Spherical tokamak work —from the development of the Spherical Tokamak Advanced Reactor in the USA for substantial reduction in weight and cost, to the Spherical Tokamak with Toroidal Magnetic Field 3 T in Mexico, continues to gain momentum. Regulatory approaches are steering away from typical nuclear fission traditions. New safety focus is emerging around transport of activated corrosion products. Outreach on the benefits of fusion must be couched in the framework of legacy, as viewed by a new generation of power stakeholders.