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Öğe Hybrid optimization and modelling of CI engine performance and emission characteristics of novel hybrid biodiesel blends(Pergamon-Elsevier Science Ltd, 2022) Viswanathan, Vinoth Kannan; Kaladgi, Abdul Razak; Thomai, Pushparaj; Ağbulut, Ümit; Alwetaishi, Mamdooh; Said, Zafar; Shaik, SaboorDifferent meta-heuristic optimization algorithms have been used in a variety of fields due to their intelligent behavior and fast convergence. However, use of these algorithms in the engine behavior optimization is very-limited. The development of so-called hybrid optimization technique when these algorithms are combined with experimental design technique is an upcoming method in the field of renewable energy. Hence in this research, meta-heuristic optimization algorithms and experimental design methods were combined to optimize the engine behavior. Additionally, artificial neural networks (ANN) were employed to forecast the performance and emission behaviors of a CI engine running on a novel hybrid biodiesel blend of Cucurbita pepo. L (pumpkin) and Prosopis juliflora, mixed with a novel Elaeocarpus ganitrus (Rudraksha) additive. To assess the success of the ANN, four statistical benchmarks (R-2, and MSE) were used. Experiments were designed according to Design of Experiments (DOE) rules with performance and emission parameters as outputs. Response surface methodology (RSM) was employed to find the effect of interaction factors. Single objective and multi-objective optimization using highly efficient hybrid RSM-particle swarm optimization (RPSO) and dragon fly algorithm (RMODA) were employed to optimize the response of the obtained RSM equations. The outcomes demonstrated that RSM and ANN were excellent modelling techniques for these kinds of situations, with good accuracy. In addition, ANN's prediction performance (R-2 = 0.978 for BTE) was somewhat better than RSM's (R-2 = 0.960 for BTE). On the other hand, the PJB20 blend with 5 mL additive increased BTE by 52.8% and reduced BSFC by 34.9% at maximum load. The smoke opacity was lowered by 7.1% when compared to pure diesel, without any engine modifications. CO2 emission was seen to be shortened by 19.14%. Finally, it can be concluded that this novel biodiesel can be possibly utilized in CI engines with no modification and the engine characteristics can be controlled by optimization and prediction models.Öğe Hydrogen Production by Water Splitting with Support of Metal and Carbon-Based Photocatalysts(American Chemical Society, 2023) Hoang, Anh Tuan; Pandey, Anand; Chen, W.-H.; Ahmed, S.F.; Ni?eti?, S.; Ng, K.H.; Said, ZafarHydrogen energy is environmental-friendly and considered an attractive alternative to fossil fuels. Among the feasible technologies for hydrogen generation, photocatalysis-derived hydrogen from water splitting is considered to be the optimal solution for meeting long-term sustainability and increased energy demands. In this context, various photocatalytic genres are proposed, with metal and carbon-supported photocatalysts demonstrating greater comprehensiveness and potential for addressing solar-driven hydrogen production from water. Several important aspects of the aforementioned photocatalytic genres are reviewed in the present work in an effort to provide pertinent researchers with new horizons for more advanced performance. The review is initiated by introducing the primary principles in photocatalysis, as well as the prerequisites for hydrogen generation from water. The focus then moves to metal-based photocatalysts, where the important features of these materials as photocatalysts are summarized. Related limitations are also discussed, along with the proposed strategies that could potentially mitigate them. Similar systematic summaries are made of knowledge on carbon-based photocatalysts. The review concludes with a discussion of potential future research directions in light of the bottlenecks currently encountered. With the proper research and development, metal-based and carbon-based photocatalysts could produce clean hydrogen from water, thereby fueling global development without causing environmental harm. © 2023 American Chemical Society.Öğe Hydrothermal carbonization of food waste as sustainable energy conversion path(Elsevier Sci Ltd, 2022) Le, Huu Son; Chen, Wei-Hsin; Ahmed, Shams Forruque; Said, Zafar; Rafa, Nazifa; Le, Anh Tuan; Ağbulut, ÜmitEvery day, a large amount of food waste (FW) is released into the environment, causing financial loss and un-predictable consequences in the world, highlighting the urgency of finding a suitable approach to treating FW. As moisture content makes up 75% of the FW, hydrothermal carbonization (HTC) is a beneficial process for the treatment of FW since it does not require extensive drying. Moreover, the process is considered favorable for carbon sequestration to mitigate climate change in comparison with other processes because the majority of the carbon in FW is integrated into hydrochar. In this work, the reaction mechanism and factors affecting the HTC of FW are scrutinized. Moreover, the physicochemical properties of products after the HTC of FW are critically presented. In general, HTC of FW is considered a promising approach aiming to attain simultaneously-two core benefits on economy and energy in the sustainable development strategy.Öğe Technological solutions for boosting hydrogen role in decarbonization strategies and net-zero goals of world shipping: Challenges and perspectives(Pergamon-Elsevier Science Ltd, 2023) Hoang, Anh Tuan; Pandey, Ashok; De Oses, Francisco Javier Martinez; Chen, Wei-Hsin; Said, Zafar; Ng, Kim Hoong; Agbulut, UemitFacing the problems concerning greenhouse gas (GHG) emissions from international ocean shipping has meant that the latest regulations of the International Maritime Organization, issued on 1st January 2023, have come into force, with the aim of reducing GHG emissions from maritime activities. Hydrogen has been suggested as an alternative fuel to achieve decarbonization ambitions in the near future. Although hydrogen has been investigated and developed over the years, its application in ocean freight is still at an embryonic stage, with a very limited number of studies exploring its feasibility. Therefore, this work comprehensively reviewed the pertinent knowledge in the field, associated with the production, storage, and energy-derivation of hydrogen on ships and aims to identify the potential issues and provide possible solutions for fueling the shipping industry with hydrogen energy. It was found that the under-par development of hydrogen-based energy for the shipping industry can be explained by the following reasons: (i) the inability of space-limited ships to use the currently available hydrogen technologies; (ii) difficulties in hydrogen storage; (iii) under-developed infrastructure at hydrogen-bunkering ports; (iv) high retrofitting, maintenance, and operating costs; (v) incomplete guidelines, international rules and regulations for the implementation of hydrogen in fueling global shipping; and (vi) cheaper conventional fuels leading to the reluctancy of industry players to become involved in such a green transition. Finally, several suggestions relating to technological aspects and policy implications were given aiming at advocating the green transition of hydrogen-powered maritime industries for cleaner and more sustainable global trading.Öğe Understanding behaviors of compression ignition engine running on metal nanoparticle additives-included fuels: A control comparison between biodiesel and diesel fuel(Elsevier Sci Ltd, 2022) Hoang, Anh Tuan; Le, Minh Xuan; Nizetic, Sandro; Huang, Zuohua; Ağbulut, Ümit; Veza, Ibham; Said, ZafarIn recent years, searching for efficient solutions to improve the emission and performance characteristics of diesel engines is considered as one of the essential and urgent work. Metal nanoparticles with a large surface area and high heat transfer coefficient could provide the impressive additive ability to the fuel reactivity and at-omization. Therefore, the critical role of metal nanoparticles in the support of diesel engine behaviors using biodiesel and diesel is thoroughly evaluated in this current review. Indeed, preparation methods and critical properties of metal nanoparticles and metal nanoparticles-laden fuels are fully introduced. More importantly, the performance, combustion, emission characteristics, and tribology behaviors of diesel engines running on metal nanoparticles-laden biodiesel are compared to diesel fuel in detail. Generally, metal nanoparticles-included biodiesel facilitates the formation of a more homogeneous oxygen-containing mixture of fuel-air, resulting in a more complete combustion process than that of diesel fuel. As a result, the use of biodiesel with the presence of metal nanoparticles is considered as the potential strategy for promoting spay and atomization, enhancing the combustion process, increasing brake thermal efficiency (BTE), reducing toxic emissions (including carbon monoxide (CO), unburnt hydrocarbon (HC), and smoke), and improving tribology characteristics. However, some drawbacks are also indicated, such as increased NOx emission and brake-specific fuel consumption. In addition, it is also concluded that studies on other environmental impacts (such as PM emission), the stable properties of metal nanoparticles, and economic aspects should be made more extensively before commercial applications of metal nanoparticles in the real world.
