The knowledge of Diesel fuel properties has great relevance for the analysis and comprehension of
phenomena related to fuel injection, fuel–air mixture formation and diesel combustion processes. This
work proposes an alternative method for estimating the bulk modulus of diesel fuels by means of an
experimental installation commonly used for determining fuel injection rates from common rail injection
systems. Three fuels were tested in the mentioned installation: commercial Diesel fuel (blended with 5.8%
of biodiesel), hydro-treated vegetal oil (HVO) and gas to liquid (GTL) fuel from natural gas by means of low
temperature Fischer Tropsch process. Results were obtained by testing two different injectors (solenoid
operated and piezoelectric injectors) under different injection pressures and energizing times. Fuel temperature
at inlet of the high pressure injection pump was controlled, keeping constant the pressure inside
the fuel injection indicator. From the experimental work, data analysis and post-processing, bulk modulus
of fuels tested has been estimated and compared to results obtained by diverse authors with different
experimental installations and methods. Results obtained in this work show small differences compared
to published data. Additionally, the initial time lag between the signal of the electric pulse when the
injector is energized and the beginning of the injection rate profile depends only on the type of injector
without influence of type of fuel and operating conditions. However, the rear time lag between both
mentioned profiles depends only on injector type (when the solenoid operated injector was tested) while,
with piezoelectric injector, it also depends on both energizing time of the injector and injection pressure.