Any alternative fuel that can replace diesel fuel in internal combustion engines need to have the same spray parameters as diesel fuel has. Spray penetration is very important and simple parameter that can easily be measured experimentally.

It is known that spray penetration increases with increasing injection pressure and depends on ambient gas conditions. However, the influence of fuel properties on spray penetration is not clear yet.

A recently developed LP-model for diesel spray penetration based on a length parameter (LP) takes into account the physical properties of fuels such as viscosity, density and surface tension. The length parameter is related to the liquid jet breakup, ligament creation, and necking.

In this paper, the model has been applied to the ECN Spray A conditions (n-dodecane with injection pressure 150 MPa and ambient gas density 22.8 kg/m3). The spray penetration under Spray A conditions calculated using the LP-model shows a good agreement with experimental data for time less than 1.2 ms.

The LP parameter was also used to calculate the Sauter mean diameter (SMD) of droplets in Spray A. The fuel viscosity has more influence on the SMD values than the density or surface tension. As a rule experimental data shows that SMD increases when the surface tension is increased. But in the case of high ambient pressure we can ignore the surface tension influence on SMD. This tendency was included in the new LP model for SMD.