Alcohol/diesel fuel blends allow reducing the formation of soot in diesel engines. However, its use in a
large scale framework still faces the challenge of high evaporative losses under storage conditions which
is hindered by the high volatility of the alcohols. Since the design of the most adequate fuelling system for
each blend requires detailed knowledge about the evaporation losses from the liquid phase, in this work a
method for calculating the evaporation of pure n-alcohols (from C1 to C5 carbon atoms) and blends of
these alcohols with ultra-low sulphur diesel (ULSD) was proposed. Alcohols vapour pressure was
determined with the Antoine equation, while the diffusion coefficient of alcohols in air was calculated
as a function of carbon number and temperature. The coefficients of activity were obtained by the
combination of continuous thermodynamic (gamma distribution function) and a modified UNIFACDortmund-Continuous
method. The evaporation losses model is based on Fick’s law and exhibited good
agreement with experimental data for all alcohols and blends at 20% content of all alcohols and at 20–60%
contents of n-butanol with diesel fuel. The evaporation was found to decrease approximately with an
inversely proportional rate with respect to the increase in the carbon chain length of the alcohol. The
paradox of faster evaporative losses from blends with lower alcohol content is explained.
2016 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license