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The sustainable utilization of waste cooking oil (WCO) as an alternative to fossil fuels has gained considerable attention due to its potential for delivering substantial environmental and economic benefits. This research attempts to explore the impact of incorporating aluminum oxide nanoparticles (AONP) into WCO on the emissions, combustion characteristics, and overall performance of a single-cylinder compression ignition (CI) engine. Comparative analyses were conducted against conventional commercial diesel fuel and pure WCO, as well as varying blends of WCO with AONP at 25 ppm, 50 ppm, and 75 ppm concentrations. The experimental results demonstrate a notable enhancement in brake thermal efficiency (BTE), with a 13.2% increase observed in the WCO + 75 AONP fuel blend compared to neat WCO. Engines fueled by WCO nanoparticle blends showed significant augmentation in-cylinder pressure and heat release rates. Furthermore, these blends exhibited a substantial reduction in carbon monoxide (CO), hydrocarbons (HC), and soot emissions by 44%, 31%, and 48%, respectively, while nitrogen oxide (NO) emissions increased by 7% compared to neat WCO. Among the assessed fuel mixtures, the WCO + 75 AONP blend demonstrated higher engine performance. This study underscores the potential of aluminum oxide nanoparticle-enhanced WCO blends as viable and environmentally responsible options for sustainable energy solutions. However, challenges such as production costs and long-term fuel stability must be addressed to establish nano-fuels as financially viable alternatives.
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Even though there is a pressing interest in clean energy sources, compression ignition (CI) engines, also called diesel engines, will remain of great importance for transportation sectors as well as for power generation in stationary applications in the foreseeable future. In order to promote applications dealing with complex diesel alternative fuels by facilitating their integration in numerical simulation, this paper targets three objectives. First, generate novel diesel fuel surrogates with more than one component. Here, five surrogates are generated using an advanced chemistry solver and are compared against three mechanisms from the literature. Second, validate the suggested reaction mechanisms (RMs) with experimental data. For this purpose, an engine configuration, which features a reacting spray flow evolving in a direct-injection (DI), single-cylinder, and four-stroke motor, is used. The RNG k-Epsilon coupled to power-law combustion models is applied to describe the complex in-cylinder turbulent reacting flow, while the hybrid Eulerian-Lagrangian Kelvin Helmholtz-Rayleigh Taylor (KH-RT) spray model is employed to capture the spray breakup. Third, highlight the impact of these surrogate fuels on the combustion properties along with the exergy of the engine. The results include distribution of temperature, pressure, heat release rate (HRR), vapor penetration length, and exergy efficiency. The effect of the surrogates on pollutant formation (NOX, CO, CO2) is also highlighted. The fifth surrogate showed 47% exergy efficiency. The fourth surrogate agreed well with the maximum experimental pressure, which equaled 85 Mpa. The first, second, and third surrogates registered 400, 316, and 276 g/kg fuel, respectively, of the total CO mass fraction at the outlet. These quantities were relatively higher compared to the fourth and fifth RMs.
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BACKGROUND: Fault-Tolerant Control Systems (FTCS) are used in critical and safety applications to improve performance and stability despite failure modes. As a result, costly production losses related to unusual and unplanned shutdowns can be prevented by incorporating these systems in the critical process plant machines. The Internal Combustion (IC) engines are highly used process plant machines and faults in their sensors will cause their shutdown instigating the need to install FTCS in them. INTRODUCTION: In this paper, an Active Fault-Tolerant Control System (AFTCS) based on a Fuzzy Logic Controller (FLC) is suggested to improve the reliability of the Air-Fuel Ratio (AFR) control system of an IC engine. METHODOLOGY: For analytical redundancy, a nonlinear Fuzzy Logic (FL) based observer is implemented in the proposed system for the Fault Detection and Isolation (FDI) unit for nonlinear sensors of the AFR system. Lyapunov stability analysis was used for designing a stable system in both faulty and normal conditions. To evaluate its performance, this system was developed in the MATLAB/Simulink platform. RESULTS: The simulation results show that the developed system is robust under sensor fault conditions, retaining stability with a minimum decrease of AFR. This study's comparison with the existing literature demonstrates that the proposed system is effective for maintaining the AFR in IC engines during sensor faulty conditions thus reducing shutdown of engine and production loss for increased profits.