It is remarkable that paraffinic fuels show better indicated efficiency because of the more centered combustion (around the Top Dead Center). Results also show that the effect of cetane number of fuels on ignition delay can be appreciated at the beginning of NEDC (1st U) and, more strongly, in the rest of the cycle. Thermodynamic diagnosis parameters have been compared, at different time windows, along the New European Driving Cycle. One of the engine cylinders was instrumented with a Kistler Kibox device combined with an opened electronic control unit and a system for online thermodynamic combustion diagnosis. Tests were carried out on a chassis dynamometer under controlled ambient conditions following the New European Driving Cycle. For this reason, this paper presents the evolution of the main parameters of the combustion process of a light-duty vehicle equipped with a Euro 4 diesel engine, operating with gas to liquid fuel, a hydrotreated vegetable oil fuel, and a commercial diesel fuel (with 5.8% of biodiesel) as reference. This knowledge allows a better calibration of engine parameters configured in the Electronic Control Unit. The knowledge of the combustion process with these fuels provides an important tool for increasing performance and for reducing pollutant emissions. The increasing interest for using alternative fuels, more environmentally friendly compared to fossil fuels, has motivated this research work. Plans for an extended experimental program are outlined. The preliminary results show promise that a useful perforating tool can be developed. DYNA2D calculations were made to assist in the interpretation of the experimental records. Static radiographs of the cavities in the sandstone showed similar cavities, however, the perforation of the steel cap was larger in response to the pellet. Perforation tests of both device configurations (with and without the pellet) into steel-jacketed sandstone cylinders were made. A time sequence of Image Intensifier Camera photographs and sequential, orthogonal flash x-ray radiographs provided information on the propagation of the foam fragments, the first shock wave disturbance, the projectile motion and deformation, and the direct shock wave transmission from the main HE charge. Two configurations were tested both had an HE annulus filled with organic foam, one had a projectile. It is an adaptation of the axial cavity in a high explosive (HE) annulus design, with the axial cavity being filled with a low density foam material. This launcher will provide an alternative technique to be used when the conventional devices do not yield the maximum well perforation. A launcher for a hypervelocity projectile to be used in well perforation applications has been designed. Shaped-charge jets are normally used in harder, more competent rock. Current oil well perforation techniques use low- to medium-velocity gun launchers for completing wells in soft rock.
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