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Novel port dual-injection (PDI) strategy helps to utilize bio-fuels, improve the performance and lower the emissions with higher mass fractions of bio-fuels. PDI strategy in SI engine allows intake manifold blending of two different fuels at any blend ratio. This paper presents the numerical study of PDI strategy using a single cylinder SI Ricardo E6 research engine. The objective of this study is to extend predictive fractal combustion model for ethanol/gasoline blends and assess the influence of ethanol (E10 to E50 mass fractions) addition to gasoline in a PDI engine. Quasi dimensional simulation is carried out using AVL Boost under wide open throttle condition at 1500 rpm. AVL Boost engine model is validated for gasoline and ethanol/gasoline pre-blends port fuel injection (PFI) with the experimental data of published literature obtained for the same engine.

Worldwide IC engine fuels are increasingly blended with oxygenate fuels to reduce the dependency on the conventional petroleum reserves. Among these fuels, biomass-derived ethanol is very popular for SI engine operation as it is not only economical and renewable source of energy, but it also allows increasing the engine performance. High latent heat of vaporization of ethanol combined with its high octane number make the engine less sensitive to knock. However, the real potential of ethanol blended fuels still has to be explored and their impact on engine combustion characterization has to be investigated. The objective of this study is to extend predictive fractal combustion model for ethanol/gasoline blends and assess the influence of ethanol addition to gasoline in a Port Fuel Injection (PFI) engine. Quasi dimensional simulation is carried out using AVL Boost under wide open throttle condition at 1500 and 3000 rpm.

Variable valve Actuation (VVA) systems are being increasingly used in IC engine. Recently novel valve actuation mechanism like continuous variable valve lift (CVVL) is being explored to regulate engine output without conventional throttle valve and this reduces the pumping losses especially at part load in SI engines. In this paper numerical model for the kinematic analysis of a CVVL mechanism is presented using MATLAB. It consists of eccentric shaft fitted with a series of intermediate rocker arm, which in turn control the degree of valve lift. The main characteristic of this mechanism is that it uses a general curve contact between the elements, which is determined using theory of envelope curve. The mechanism’s system of equations solving principle is based on the Newton-Raphson numerical method.