This paper deals with the technical feasibility of the use of straight vegetable oil (SVO) as gas turbine fuels.\ud First, this paper reports the results of the experimental characterization of different vegetable oils, derived from energy crops, and of blends of diesel and vegetable oil in different concentrations (from pure diesel to pure vegetable oil). The considered vegetable oils were obtained from different types of oilseeds (rapeseed, sunflower, soybean) and were cultivated under different agronomic scenarios. The SVO properties determined experimentally are SVO elemental composition, lower heating value, density, specific heat and viscosity, for which this paper provides a practical overview, coming both from experiments and literature data.\ud Secondly, the paper experimentally evaluates the behavior of a Solar T-62T-32 micro gas turbine fed by vegetable oils. The vegetable oils are supplied to the micro gas turbine as blends of diesel and straight vegetable oils in different concentrations, up to pure vegetable oil. The paper describes the test rig used for the experimental activity and reports some experimental results, which highlight the effects of the different fuels on micro gas turbine performance and pollutant emissions

In recent years, the interest in the research on energy production systems fed by biofuels has increased. Gaseous fuels obtained through biomass conversion processes such as gasification, pyrolysis and pyrogasification are generally defined as synthesis gas (syngas). The use of synthesis gas in small-size energy systems, such as those used for distributed micro-cogeneration, has not yet reached a level of technological maturity that could allow a large market diffusion. For this reason, further analyses (both experimental and numerical) have to be carried out to allow these technologies to achieve performance and reliability typical of established technologies based on traditional fuels. In this paper, a numerical analysis of a combustor of a 100-kW micro gas turbine fed by natural gas and biomass-derived synthesis gas is presented. The work has been developed in the framework of a collaboration between the Engineering Department of the University of Ferrara, the Istituto Motori - CNR (Napoli), and Turbec S.p A. of Corporeno di Cento (FE). The main features of the micro gas turbine Turbec T100, located at the Istituto Motori - CNR, are firstly described. A decompression and distribution system allows the feeding of the micro gas turbine with gaseous fuels characterized by different compositions. Moreover, a system of remote monitoring and control together with a data transfer system has been developed in order to set the operative parameters of the machine. The results of the tests performed under different operating conditions are then presented. Subsequently, the paper presents the numerical analysis of a model of the micro gas turbine combustor. The combustor model is validated against manufacturer performance data and experimental data with respect to steady state performance, i.e., average outlet temperature and emission levels. A sensitivity analysis on the model capability to simulate different operating conditions is then performed. The combustor model is used to simulate the combustion of a syngas, composed of different ratios of hydrogen, carbon monoxide, methane, carbon dioxide and water. The results in terms of flame displacement, temperature and emission distribution and values are analyzed and compared to the natural gas simulations. Finally, some simple modifications to the combustion chamber are proposed and simulated both with natural gas and syngas feeding

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In recent years, the interest in the research on energy production systems fed by biofuels is increased. Gaseous fuels obtained through biomass conversion processes such as gasification, pyrolysis and pyrogasification are generally defined as synthesis gas. The use of synthesis gas in small-size energy systems, such as those used for distributed micro-cogeneration, has not yet reached a level of technological maturity that could allow a large market diffusion. For this reason, further analyses (both experimental and numerical) have to be carried out to allow these technologies to achieve performance and reliability typical of established technologies based on traditional fuels. In this paper, an experimental and numerical analysis of a combustor of a 100-kW Micro Gas Turbine fed by synthesis gas is presented. The work has been developed in the framework of a collaboration among the Department of Engineering of the University of Ferrara, the Istituto Motori CNR of Naples, and Turbec SpA of Cento (FE). The main features of the microturbine MGT Turbec T100, located at the Istituto Motori CNR of Naples, are firstly described. A decompression and distribution system allows to feed the MGT with gaseous fuels characterized by different compositions. Moreover, a system of remote monitoring and control together with a data transfer system have been developed in order to set the operative parameters of the machine for the current test. The results of the tests performed under different operating conditions are then presented. Subsequently, the paper presents the numerical analysis of a model of the MGT combustor. The combustor model is validated against manufacturer performance data and experimental data with respect to steady state performance, i.e. average outlet temperature, emission levels, pressure drops. Then, a syngas, composed by different ratios of hydrogen, carbon monoxide, methane, carbon dioxide and water, is simulated and the results analyzed.

Current energy policies tend to encourage the production of renewable energy for environmental reasons and energy independence. Among renewable sources, biomass can play a key role, because of economic, environmental and political factors, such as the need to diversify and improve energy supply, reduce the greenhouse effect and support rural areas. For the case of liquid biofuels derived from agricultural crops, several possibilities can be considered, such as straight vegetable oil (SVO), oil-derived esters, bioethanol or blends with conventional fuels (diesel or gasoline). The use of SVOs and their derivatives usually poses some problems, that essentially derive from their much higher viscosity and higher boiling temperature. In order to evaluate the technical feasibility of the use of SVOs within gas turbine combustors, this paper reports the results of the experimental characterization of different vegetable oils, derived from dedicated crops. Moreover, blends composed of diesel and vegetable oil in different concentrations (from pure diesel to pure vegetable oil) are also considered and their experimental characterization is also reported, with particular focus on blend viscosity. The considered vegetable oils were obtained from different types of oilseeds (rapeseed, sunflower, soybean) and were cultivated under different agronomic scenarios. The SVO properties determined experimentally are SVO elemental composition, lower heating value, density, specific heat and viscosity, for which this paper provides a practical overview, coming both from experiments and literature data.