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The 2022 G20 Summit agenda emphasized a sustainable energy transition to solve global complex issues. Multidisciplinary energy transition planning and execution incorporate chemistry. A sustainable energy transition depends on thermochemistry issues and applications, which must be assessed from heat, fuel combustion efficiency, environmental, economic, and social viewpoints. A three-week thermochemistry course at Universitas Negeri Malang taught undergraduate chemistry students how chemistry helps solve SDGs problems. This quasi-experimental pretest-posttest control group study assessed digital literacy and scientific argumentation. Digital literacy was examined using a two-tier hydrogen fuel test instrument (r=0.947) and scientific argumentation with an argumentation skills test instrument (r=0.855). Digital literacy is largely foundation (level 1) and intermediate (level 2), however 8.6% of students can argue scientifically. After studying about the energy transition using Argumentation and Digital Literacy (ADL), students’ digital literacy improved to advanced level and 68.5% of their responses were higher-level arguments. Learning treatment’s impact on digital literacy and scientific reasoning was quantified using a paired-sample t-test and N-Gain Score. The moderate N-Gain values of 0.58 and 0.56 demonstrate that SDG-based learning strategies can significantly increase scientific argumentation and digital literacy.

To measure the heat generation rate of nuclear fuel rods during an irradiation test, the temperature deviation of the coolant that passes by the fuel rod and its flow velocity need to be measured. Although the temperature of the coolant can be measured by thermocouples instrumented in the nuclear fuel test rig, the flowrate of the coolant is difficult to measure owing to the narrow space of the test rig. Therefore, a noise analysis technique using fluctuation signals from thermocouples installed at both end parts of the fuel rod has been developed by several advanced groups. Although the noise analysis technique was also developed at the Korea Atomic Energy Research Institute, out of pile test results showed that the accuracy of the coolant flow measurement was more than 40%. In this study, the ground pattern of the control board and earth connection are enhanced to eliminate external noise. In addition, a heater unit is installed in the coolant flow simulator to obtain a strong fluctuation signal from the coolant. Thus, the coolant flow simulator is improved, and the accuracy of the coolant flow measurement shows an error of less than 5%.

The heat generation rate is one of the most important characteristics in evaluating the performance of nuclear fuel. The heat generation rate of a nuclear fuel rod can be measured indirectly by calculating the heat flux that coolant absorbs while passing by the nuclear fuel rod. To calculate the heat flux from the fuel rod, it is necessary to measure the temperature deviation and flow velocity at both end parts of the fuel rod. Thus, measuring the flow velocity in the test rig during the irradiation test of nuclear fuel is important to measure the heat generation rate. In this study, a cross correlation technique that uses signals obtained from two thermocouples instrumented at both end parts of the fuel rod has been developed to measure the flow velocity of coolant in the test rig.

With the aviation industry facing increasing environmental and energy challenges, there has been a growing demand for sustainable aviation fuel (SAF). Previous studies have shown the role of ice accretion, release and blockage in aviation-related incidents and accidents with conventional jet fuel. However, there is no available data that establishes the magnitude of influence new fuel compositions will pose on ice formation and accretion in aircraft fuel systems. A recirculating fuel test rig capable of cooling fuel from ambient to −30°C within 4h was built by Airbus to simulate conditions in an aircraft wing tank and allow characterisation of ice accretion. The key characteristic was the pressure drop across an inline fuel strainer for the different SAF explored but visual analysis of ice accretion on the strainer mesh (filters used in protecting fuel feed pumps) was also performed for individual experimental runs for comparison. Measurements revealed that 100% conventional fuel exhibited a higher propensity to strainer blockage compared to the SAF tested. However, all SAF blends behaved differently as the blending ratio with Jet A-1 fuel had an impact on the pressure differential at different temperatures. Data from this work are essential to establish confidence in the safe operation of future aircraft fuel systems that will potentially be compatible with 100 % SAF.

RCCI is a promising combustion strategy that can improve the controllability of combustion phasing. This study evaluates fusel oil (an inexpensive industrial by-product) as a low-reactivity supplementary fuel in an RCCI diesel engine. Fusel oil was injected into the intake air at 4, 6, 10, 12, and 16 g/min (DF4-DF16), and experiments were conducted on a four-cylinder, four-stroke diesel engine at 1750 rpm under 40, 60, 80, and 100 Nm. In-cylinder temperature/pressure-based combustion behaviour, air excess ratio (λ), NO and smoke emissions were assessed. The influence of fusel oil on combustion was strongest at low load. At 40 Nm, the highest fusel-oil energy share increased peak cylinder pressure by 14% and peak in-cylinder temperature by 4% compared to diesel fuel tests, while at 100 Nm the corresponding increases were 4% and less than 1%. NO increased at 40 Nm, with a maximum rise of 17.9% at the highest fusel-oil energy share, but decreased at medium and high loads, falling by 7.13 to 13.54% between 60 and 100 Nm. Smoke increased consistently with fusel oil, reaching about 42% at 40 Nm and remaining below 22% at 100 Nm. A techno-economic assessment showed that although capital costs increased slightly, the low price of fusel oil decreased operating costs by up to 33% and reduced life-cycle costs by up to 42%. Overall, fusel oil-assisted RCCI operation can provide notable cost benefits and conditional NO reductions, though with a smoke penalty that should be considered in application and after-treatment strategies.

Low-Speed Pre-ignition (LSPI) is an undesirable abnormal combustion phenomenon observed in turbocharged, direct-injection spark-ignition engines and is characterized by early heat release, high cylinder pressures and severe, potentially damaging knock. LSPI has been studied for more than a decade and engine design, operating conditions and fuel and engine oil formulations have all been identified as contributing factors. A significant focus on engine oil has led to the establishment of the Sequence IX engine test and the second-generation of GM dexos® oil requirements, as well as a convergence of engine oil detergent causality. Conclusions about the effects of fuel on LSPI have been more varied, but as part of a recently completed research consortium, the LSPI tendency of market fuels with a range of properties, including composition, boiling point distribution, ethanol content and particulate matter index (PMI) were evaluated. Tests were performed in a 2-liter GM LHU engine and each test comprised of at least 24 repeats of a high-load, low-speed, steady-state test segment, with engine boundary conditions and calibration adjusted to amplify LSPI. All market fuel tests were bracketed by baseline tests and severity adjustments were made to account for changes in engine condition. It was found that the PMI and certain boiling points correlated the best with the frequency of LSPI events. In addition, decreased LSPI severity, quantified by the peak-to-peak knock values, was found to correspond with increased octane numbers and higher ethanol content of the market fuels.

Evaluation of combustion characteristic, engine performances and exhaust emissions of nanoparticles blended in palm oil methyl ester (POME) was conducted in this experiment using a single-cylinder diesel engine. Nanoparticles used was aluminium oxide (Al2O3) and silicon dioxide (SiO2) with a portion of 50 ppm and 100 ppm. SiO2 and Al2O3 were blended in POME and labelled as PS50, PS100 and PA50, PA100, respectively. The data results for PS and PA fuel were compared to POME test fuel. Single cylinder diesel engine YANMAR TF120M attached with DEWESoft data acquisition module (DAQ) model SIRIUSi-HS was used in this experiment. Various engine loads of zero, 7 N.m, 14 Nm, 21 N.m and 28 N.m at a constant engine speed of 1800 rpm were applied during engine testing. Results for each fuel were obtained by calculating the average three times repetition of engine testing. Findings show that the highest maximum pressure of nanoparticles fuel increase by 16.3% compared to POME test fuel. Other than that, the engine peak torque and engine power show a significant increase by 43% and 44%, respectively, recorded during the PS50 fuel test. Meanwhile, emissions of nanoparticles fuel show a large decrease by 10% of oxide of nitrogen (NOx), 6.3% reduction of carbon dioxide (CO2) and a slight decrease of 0.02% on carbon monoxide (CO). Addition of nanoparticles in biodiesel show positive improvements when used in diesel engines and further details were discussed.  

Robust numerical tools are essential for enabling the use of hybrid rocket engines (HREs) in future space applications. In this context, Computational Fluid Dynamics (CFD) transient simulations can be employed to analyse and predict relevant fluid dynamics phenomena within the thrust chamber of small-scale HREs. This work applies such techniques to investigate two unexpected behaviours observed in a 10 N-class hydrogen peroxide-based hybrid thruster: an uneven regression rate during High-Density Polyethylene (HDPE) and Acrylonitrile Butadiene Styrene (ABS) fuel tests, and non-negligible axial consumption in the ABS test case. The present study seeks to identify their fluid-dynamic origins by analysing key aspects of the thruster’s internal ballistics. The impact of recirculation zones and mixing on regression rates is quantified, as is the effect of grain heating on performance. Although already known in the present scientific literature, these phenomena prove to become particularly relevant for small-scale engines. Furthermore, the study demonstrates how appropriate numerical tools can replicate experimental findings, helping to foresee and mitigate undesirable behaviours in the design phases of future HRE propulsion systems. CFD results match the final HDPE grain geometry, reproducing the uneven port diameters with a maximum error below 9%. For ABS, axial regression is accurately captured, confirming the model’s reliability. Furthermore, average regression rates differ by only 1.60% and 1.20% for HDPE and ABS, respectively, while mass consumption is reproduced within 1.70% for HDPE and 3.01% for ABS. Overall, the results of the work demonstrate the reliability of the numerical approach adopted. This enriches the analysis capabilities devoted to 10 N-class engines, provides an additional tool for simulating the internal ballistics of small-scale hybrid thrusters, and integrates the existing literature with new insights into their fluid dynamics.

In light of the ‘dual carbon’ policy and the increasing need for clean energy applications, enhancing the combustion efficiency and emission management of heavy‐duty natural gas engines has emerged as a critical issue necessitating immediate advancements. This paper addresses the challenges encountered by heavy‐duty engines regarding high‐efficiency combustion across a broad load spectrum. It proposes a multi‐stage thermally coupled combustion strategy that integrates trace diesel ignition with quasi‐homogeneous combustion of natural gas, with the objective of achieving high efficiency, low emissions, and stable combustion from medium‐low loads up to the 19.5 bar IMEPg range. The dynamic regulation of in‐cylinder thermodynamic activity was achieved by adjusting boundary conditions, including the excess air coefficient (λ), exhaust gas recirculation (EGR) rate, and injection time. The findings indicate that the engine can attain a maximum indicated thermal efficiency of 49.6%, provided that the peak cylinder pressure remains below 16.5 MPa and the knock index RI is under 5 MW/m2, while simultaneously demonstrating exceptional emission performance with near‐zero carbon smoke emissions and NOx levels below 0.4 g/kWh. The combustion process may be categorised into three stages based on cylinder pressure and exothermic rate partitioning analysis: initial diesel ignition and exothermic reaction, flame propagation and thermal atmosphere preparation, and auto‐ignition of the primary combustion mixture. The medium‐temperature exothermic process in the second stage is crucial for modulating the auto‐ignition phase and controlling the combustion rate. This paper integrates the fundamental concepts of TAC‐HCCI and DING‐EDI combustion modes to establish a cohesive three‐phase thermodynamic coupling mechanism, culminating in a closed‐loop system for theoretical modelling and experimental validation on a single‐cylinder dual‐fuel test platform. The identification of combustion characteristic points (t1, t2, t3) and the development of ITEg‐emission profiles validate the alignment between the theoretical model and real test data, while also achieving the categorisation and optimisation of combustion mode extraction. In contrast to the conventional dual‐fuel combustion strategy, the method proposed in this study demonstrates enhanced flexibility and adaptability regarding high‐load expansion capability, emission optimisation potential, and stability at low and medium loads, thereby offering novel theoretical support and a technological pathway for the efficient and low‐carbon advancement of natural gas engines. This paper addresses the challenges encountered by heavy‐duty engines regarding high‐efficiency combustion across a broad load spectrum. It proposes a multi‐stage thermally coupled combustion strategy that integrates trace diesel ignition with quasi‐homogeneous combustion of natural gas.

Iron aluminides possess a unique combination of properties such as attractive corrosion resistance in hot gas and wet chemical environments, a favorable strength to weight ratio, low costs of alloying elements, and they can be processed by conventional methods. For the current study, a promising iron aluminide (Fe-Al-Mo-Ti-B) was employed, which shows the potential to replace costly heat resistant steels or expensive Ni-based alloys for components in large bore two-stroke marine engines. The prechamber, an integral part of the combustion system of dual fuel two-stroke marine engines, which must withstand harsh conditions, was selected as the component. Prototypes made of the novel iron aluminide were manufactured via investment casting and hot isostatic pressing using powder of the intermetallic alloy. The high temperature oxidation behavior, the wet corrosion resistance in acid media, and the mechanical properties up to 700 °C were evaluated. A prototype of the prechamber was tested on a large bore two-stroke dual fuel test engine and post analysis of the tested component was performed. The results show that the employed iron aluminide alloy could be an economic alternative to the currently used Ni-based alloy.