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Lithium-ion cells operate under a narrow range of voltage, current, and temperature limits, which requires a battery management system (BMS) to sense, control, and balance the battery pack. The state of power (SOP) estimation is a fundamental algorithm of the BMS. It operates as a dynamic safety limit, preventing rapid ageing and optimizing power delivery. SOP estimation relies on predictive algorithms to determine charge and discharge power limits sustainable within a specified time frame, ensuring the cell design constraints are not violated. This paper explores various approaches for real-time deployment of SOP estimation algorithms for a high-power lithium-ion battery (LIB) with a low-cost microcontroller. The algorithms are based on a root-finding approach and a first-order equivalent circuit model (ECM) of the battery.

The number of electric vehicles is increasing in line with the global carbon reduction targets. More households are installing electric charging points to complement the existing charging infrastructure. The increasing electricity prices affected by the global energy/economic crisis however pushed more households towards coupling their charging points with renewable energy generation and storage systems to manage the supply and demand of energy more effectively. In this study, an electric charging station equipped with Photovoltaic panels and an electric storage system utilising second-life Electric Vehicles (EV) batteries is designed and analysed. Various electricity generation capacities are considered to be installed on the roof of the case study building ranging from 5m2 and 20m2. The second-life batteries are disposed from EVs with an 80% state of health. MATLAB Simulink is used for mathematical modelling of system.

A semi phenomenological and global chemical kinetic model is adopted and applied to predict soot formation in gasoline-fueled spark ignition engines. The adopted model considers acetylene produced from gasoline pyrolysis process as the main precursor for soot inception. The adopted soot model was initially proposed for diffusion flames and this work tries to apply and modify it to gasoline fueled (premixed flame) spark ignition engines. The burned mass fraction and burn rate are used to estimate the instantaneous acetylene, oxygen and Hydroxyl (OH) radical mass fractions at each crank angle of the engine. Experimental data from a single point throttle body injected spark ignition engine is used for validating total particle numbers at different engine operating conditions. The simulation results agree reasonably with the experimental results. Both experimental and predicted results showed that the inception rate increases with the engine load in an exponential form.

This work aimed to study nano-scale particulate matter originating from gasoline direct injection engine during cold start and warm up operating conditions and to identify the role of the three-way catalytic converter on nano-scale particulate during cold-start and warm-up operating conditions. This work used a 4-stroke, 1.6 litre, wall guided gasoline direct injected, turbocharged and intercooled SI engine equipped with a three-way catalytic converter for this investigation. It used a fast particle spectrometer for the measurement of exhaust nano-scale particles upto 1000 nm diameter.

This work experimentally investigated the combustion characteristics and cycle-by-cycle variations of a turbocharged, intercooled, gasoline direct injected spark ignition (DISI) engine at a wide range of operating conditions. The cycle-by-cycle variations have been characterized by the coefficient of variance of (COV) cylinder pressure against crank angle, the indicated mean effective pressure (IMEP) and 50% mass fraction burned. The combustion characteristics and cyclic variability of the DISI engine are compared with data from throttle body injected engines throughout the analysis to draw conclusions. The present work identified that the COV of pressure reaches a minimum value at the end of the compression stroke and this minimum value is independent of engine type and the loading conditions investigated. It also identified that the maximum COV value of the pressure against crank angle during combustion does not change significantly with load for the throttle body injected engine.

This work attempted to correlate the ultra fine particulate count to the flame propagation time, in-cylinder peak pressure, and in-cylinder ageing time (the time the particulates stay inside the cylinder) of a throttle body gasoline injected engine. The engine was tested at different loads and speeds ranging from 20 Nm to 100 Nm and 2000 to 3400 rpm respectively. A fast particle spectrometer, a mass spectrometer, and an in-cylinder pressure measurement system were used to characterize the particulate emission. This work identified the correlation between the nucleation of particulates and rate of burning, the particulate count for particles size greater than 200 nm and the in-cylinder ageing time. It identified that an increase in engine load at constant speed increased the particle number density of the 10 nm diameter particles; the effect was less significant on the particles of diameter greater than 50 nm and almost absent on particles of diameter greater than 200 nm.

This study attempted to identify the correlation between the gaseous species and nano-scale exhaust particles from a gasoline engine using simultaneous particulate and gaseous measurement. A fast particle spectrometer for particulates and a quadrupole mass spectrometer for gaseous species were employed in this work. Two commercially available super unleaded gasoline fuels were used in this study to establish a link between the gaseous species and nano-scale particulates. The possible correlations between the gaseous species such as acetylene, 1, 5 hexadyne, toluene, benzene and furaldehyde and nano-scale particles were identified and are detailed in this paper.

The present work evaluated the performance of a EURO-IV vehicle for real-world driving in Mexico City. This work also attempted to identify if it was possible to reduce green house gas emission and fuel consumption for real-world driving in Mexico City by using vehicle technology available in EURO-IV certified vehicles. It used three different drive cycles representing typical driving conditions in North, South and Central zones of Mexico City. These drive cycles were developed using a single instrumented-experimental vehicle and the data collected from 200 trips over a year covering peak and off-peak driving conditions. This work used a vehicle-powertrain model of a EURO-IV vehicle, which was validated by the authors using experimental data for four other drive cycles that represented typical driving conditions in the United Kingdom.

Recent developments in measurement techniques enabled researchers to measure ultra-fine particulates of nano-scale range and provided more evidence that the smaller particulates typically emitted from gasoline engines may have more severe impacts on human respiratory system than the bigger particulates from diesel engines. The knowledge of the characteristics of particulates from gasoline engines, especially, the effect of fuel borne additives is sparse. This work presents the findings from a study into the effect of aftermarket additives on nano-scale particulates. Four commercially available fuel borne additives used in gasoline engines mainly by private vehicle owners in the United Kingdom were selected for this study. The combustion and emission performance of the additive fuels were compared against that of commercially available gasoline fuel using a 4-stroke, throttle body injected gasoline engine.

The work presented investigates the effect of road gradient, head-wind, horizontal road curvature, changes in tyre rolling radius, vehicle drag co-efficient and vehicle weight on real-world emission levels of a modern EURO-IV vehicle. A validated steady-state engine performance map based vehicle modeling approach has been used for the analysis. The results showed that a generalized correction factor to include the effect of road-gradient on real-world emission levels might not yield accurate results, since the emission levels are strongly dependent on the position of the vehicle operating parameters on the engine maps. In addition, it also demonstrated that the inclusion of horizontal road curvature such as roundabouts and traffic islands are essential for the estimation of the real-world emission levels.

The clutch of an F1 car is a key component in the achievement of a successful launch. At this point, the clutch will do more work than at any other time during the race. The clutch can be held slipping for up to 8 seconds, causing considerable heat generation in the friction plates. This paper describes an investigation of the thermal mechanics of the clutch during the launch, and how the heat generated by the period of slipping could affect the frictional properties of the clutch plates. Using a simple single-plate clutch, data from a clutch dynamometer has been accumulated over a range of launch scenarios, including re-starts and short and long slip periods. By analyzing and comparing the data, a wider range of clutch scenarios can be evaluated, including the effects of varying the design parameters of the clutch, along with a more detailed investigation into the effects of banding upon the friction plates.

Cast iron brake discs are commonly used for road and race applications. The graphite flake arrangement of grey cast iron matches the high thermal conductivity requirements of brake discs, although with the brittleness characteristic of this material. Therefore the design of cast iron brake discs is a compromise between a thermally efficient design to reduce the operating temperature and a design generating a controlled tensile stress level to prevent crack failure, with as little mass penalty as possible. The most critical failure mode on competition brake discs is catastrophic crack propagation in the early stages of service life. Dynamometer testing has shown that the initial bedding process greatly reduces the likelihood of catastrophic disc failure. This fact leads to the hypothesis that a heat treatment process occurs on the discs during bedding, increasing their crack resistance.

This paper investigates the effect of tailpipe orientation on carbon monoxide (CO) dispersion patterns which is directly linked to the CO exposure levels that a cyclist can experience in Oxford City. The most common tailpipe orientations used in Oxford city vehicles have been identified. Following this, the dispersion patterns from various tailpipe orientations were experimentally investigated and the results used to construct contour maps of CO dispersion patterns. The contour maps were used to estimate the likely exposure levels a cyclist can experience. The real-world cyclist CO exposure levels were also measured in two routes in Oxford city and compared with those obtained from the contour maps and data from fixed site monitoring station. The results show that CO levels in the cycle lane are significantly affected by the tailpipe orientation and are higher than the recommended World Health Organization (WHO) exposure levels.

The present work investigated the real-world emission performance of a typical light-duty gasoline vehicle to identify the most significant vehicle operating parameter responsible for excessive real-world emission levels. Based upon tailpipe-out emission levels two distinct portions in the engine maps could be identified; a clean portion of the map, which covers the engine operating points within the European the legislative drive cycle, and an unclean portion of the map that is outside the legislative testing. A systematic investigation of the tailpipe-out emission levels for the real-world drive cycle showed that the levels of vehicle speed and acceleration are immaterial if the vehicle operating points remain within the cleaner zone of the engine map. The methodical approach followed to identify the most significant vehicle operating parameter responsible for the real-world emission levels is given in this paper.

This paper investigates an approach to modelling real-world drive cycles for the prediction of fuel economy and emission levels. It demonstrates that a steady-state engine performance data based modelling approach can be used for real-world drive cycle simulation. It identifies and demonstrates that a steady-state performance data-based approach is the only current viable approach for real-world tailpipe-out CO level predictions. It also identifies quantitatively the difference between the modal emission measurements and constant volume sampling (CVS) bag values for emission modelling validation. A systematic validation and sensitivity analysis of the modelling approach is also described.