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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.

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.

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 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 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.

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.