Bad Bad Bad Biodiesel for VW TDIs

Vegetable oils were used already briefly into combustion engines after their invention [ 3 ]. Conditionally urch the rapidly using development of the oil industry and the availability of cheap fuels were not competitive such products and played therefore up to?Energiekrise so mentioned? Beginning of the 70's and the environmental awareness no role arising at the same time. Fuels on vegetable oil basis offer advantages due to the molecularly bound oxygen regarding the emission behavior (in particular soot) opposite conventional fuels. Besides agrarian aspects promote the cultivation of regenerativ energies, for example as alternative to raemienbeguenstigter field fallowing and/or high-subsidized export of agricultural products. FAME (Fatty Acid methyl of Ester) fuels animal or vegetable fats and oils can have as starting point. RWS methyl ester (RME) is thereby and the furthest common fuel on plant basis, most well-known in Europe. Such fuels are very critical for the injection system, since they attack elastomers and plastics. Free fatty acids, vinegar and formic acid as well as methanol entail corrosion, free glycerin and glyzeride attack NE metals and can to deposits, fig. 21, and to clogging the fuel filter lead. Due to the high modulus of elasticity, compared with Diesel fuel, partial higher injection pressures, which can lead to a reduction of the life span, result. The use of company ME fuel is particularly in the agrarian range far common. Due to oxidation stability smaller compared with Diesel fuel the downtimes often long in the this sector are critical (for example with combines). With a verteilereinspritzpumpe few days were?verklebt with one another after completion of a permanent run all construction units in direct contact? to solve and only under employment of appropriate solvents again. In order to prevent this, in time the entire fuel cycle with Diesel fuel is to be rinsed before the putting out of operation. Problematic is also the changing refueling with FAME and Diesel fuel (Diesel company ME mixtures). Problems, which arise in the permanent run enterprise with pure fuel, place themselves with mixtures in somewhat weakened form and after somewhat longer period of operation likewise [ 4 ]. Beyond that for example a clearly higher solution ability for water than Diesel fuel has RME (1000 ppm to 200 ppm). Different mixing proportion by addition of Diesel fuel lead to the separation and with it to the education of free water and with it connected the problems.

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Requirements of injection systems for commercial motor vehicle diesel engines

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