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An algal feedstock or biomass may contain a very high oil fraction, and thus could be used for the production of advanced biofuels via different conversion processes. Its major advantage apart from its large oil fraction is the ability to convert almost all the energy from the feedstock into different varieties of useful products. In the research to displace fossil fuels, algae feedstock has emerged as a suitable candidate not only because of its renewable and sustainable features but also for its economic credibility based on the potential to match up with the global demand for transportation fuels. Cultivating this feedstock is very easy and could be developed with little or even no supervision, with the aid of wastewater not suitable for human consumption while absorbing CO2 from the atmosphere. The overall potential for algae applications generally shows that this feedstock is still an untapped resource, and it could be of huge commercial benefits to the global economy at large because algae exist in millions compared to terrestrial plants. Algae applications are evident for everyday consumption via foods products, non-foods products, fuel, and energy. Biofuels derived from algae have no impact on the environment and the food supply unlike biofuels produced from crops. However, any cultivation method employed could control the operating cost and the technicalities involved, which will also influence the production rate and strain. The scope of this paper is to review the current status of algae as a potential feedstock with diverse benefit for the resolution of the global energy demand, and environmental pollution control of GHG.

The paper discusses the concept, design and final results from the 'Ultra Boost for Economy' collaborative project, which was part-funded by the Technology Strategy Board, the UK's innovation agency. The project comprised industry-and academiawide expertise to demonstrate that it is possible to reduce engine capacity by 60% and still achieve the torque curve of a modern, large-capacity naturally-aspirated engine, while encompassing the attributes necessary to employ such a concept in premium vehicles.In addition to achieving the torque curve of the Jaguar Land Rover naturally-aspirated 5.0 litre V8 engine (which included generating 25 bar BMEP at 1000 rpm), the main project target was to show that such a downsized engine could, in itself, provide a major proportion of a route towards a 35% reduction in vehicle tailpipe CO 2 on the New European Drive Cycle, together with some vehicle-based modifications and the assumption of stop-start technology being used instead of hybridization. In order to do this vehicle modelling was employed to set part-load operating points representative of a target vehicle and to provide weighting factors for those points. The engine was sized by using the fuel consumption improvement targets and a series of specification steps designed to ensure that the required full-load performance and driveability could be achieved.The engine was designed in parallel with 1-D modelling which helped to combine the various technology packages of the project, including the specification of an advanced charging system and the provision of the necessary variability in the valvetrain system. An advanced intake port was designed in order to ensure the necessary flow rate and the charge motion to provide fuel mixing and help suppress knock, and was subjected to a full transient CFD analysis. A new engine management system was provided which necessarily had to be capable of controlling many functions, including a supercharger engagement clutch and full bypass system, direct injection system, port-fuel injection system, separately-switchable cam profiles for the intake and exhaust valves and wide-range fast-acting camshaft phasing devices.

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The paper is concerned with the effects of cyclic variation in turbulence (expressed in terms of rms turbulent velocity) on the burn rate and subsequent cyclic variation in in-cylinder pressure derived parameters. The task has been addressed by applying a thermodynamic engine modelling approach for simulations of two very different engines; a single cylinder research engine in which sources of cyclic variation other than turbulence had been minimised and a multi-cylinder production engine. The cyclic variability in the two engines had a number of similar features; the effects of turbulence variation cycle-to-cycle proved dominant in the production engine, mixture strength secondary and prior-cycle residual concentration feedback marginal.

The impact of n-butanol blending on the combustion, autoignition and knock properties of gasoline has been investigated under supercharged spark ignition engine conditions for stoichiometric fuel/air mixtures at intake temperature and pressure conditions of 320 K and 1.6 bar, respectively, for a range of spark timings. A toluene reference fuel (TRF) surrogate for gasoline containing toluene, n-heptane and iso-octane has been tested experimentally in the Leeds University Ported Optical Engine (LUPOE) alongside a reference gasoline and their blends (20 % n-butanol and 80 % gasoline/TRF by volume). Although the gasoline/n-butanol blend displayed the highest burning rate, and consequently the highest peak pressures compared to gasoline, TRF and the TRF/n-butanol blend, it exhibited the least propensity to knock, indicating that addition of n-butanol provides an opportunity for enhancing the knock resistance of gasoline as well as improving engine efficiency via the use of higher compression ratios. The anti-knock enhancing quality of n-butanol on gasoline was however observed to weaken at later spark timings. Hence, whilst n-butanol has shown some promise based on the current study, its application as an octane enhancer for gasoline under real engine conditions may be somewhat limited at the studied blending ratio. As expected based on previous ignition delay studies, the TRF showed an earlier knocking boundary than the rest of the fuels, which may possibly be attributed to the absence of an oxygenate (ethanol or n-butanol) as present in the other fuels and a lower octane index. Overall, the TRF mixture gave a reasonable representation of the reference gasoline in terms of the produced knock onsets at the later spark timings for the pure fuels. However, on blending, the TRF did not reproduce the trend for the gasoline at later spark timings which can be linked to difficulties in capturing the temperature trends in ignition delays around the negative temperature coefficient region observed in previous work in a rapid compression machine (

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