**4. Conclusion**

An Eulerian/Lagragian approach has been presented to calculate evaporating sprays through a crossflow. A method developed to study isothermal turbulent two- and threedimensional dispersion was extended to the case of an array of evaporating biofuel droplets.

The droplet diameter, temperature and mass fraction distributions were found to be strongly dependent on the fuels used. Rapeseed Methyl Esters exhibit similar evaporating characteristics to DF-2, which indicates that it can be successfully used as an alternative fuel in many applications that utilize diffusion flames. The use of RME in homogeneous combustion systems may require a prohibitive level of pre-heating, and the use of Ethanol (obtained from sugar or starch crops) may be a better alternative.

### **5. Aknowledgements**

The present work has been performed in the scope of the activities of the AFTUR project. The financial support of the European Commission under Contract nº ENK5-CT-2002-00662 is gratefully acknowledged.

#### **6. References**

118 Fuel Injection in Automotive Engineering

diameter, d 230,3m 230,3m 230,3m 230,3m 230,3<sup>m</sup>

Rapeseed Methyl ester (RME)

10m/s 10m/s 10m/s 10m/s 10m/s

800ºK 800ºK 800ºK 800ºK 800ºK

800ºK 800ºK 800ºK 800ºK 800ºK


293ºK 293ºK 443ºK 293ºK 293ºK

1 bar 101 350Pa Diesel fuel

1 bar 101 350Pa

1 bar 101 350Pa

Kg/s

(DF-2) Ethanol

Rapeseed Methyl ester (RME)

> 1 bar 101 350Pa

quite similar to those obtained with more volatile fuels such as n-Heptane or Ethanol.

Mass loading 20x10-4 Kg/s 20x10-4 Kg/s 20x10-4 Kg/s 20x10-4 Kg/s 20x10-4

The evaporative characteristics of RME can be further analysed with the help of Fig.6 that shows a three-dimensional perspective of the mass fraction distribution with and without additional pre-heating. The results obtained with DF-2 and RME without additional preheating (Figs.6a and b) show that the mass fraction of fuel is always less than 0.04. For the DF-2 there is a larger evaporation near the injector, but further downstream the RME gives the higher values. When the additional pre-heating of 150K is used with RME, the domain shows a large region with a concentration of fuel vapour greater than 0.06, and the resulting pattern is

An Eulerian/Lagragian approach has been presented to calculate evaporating sprays through a crossflow. A method developed to study isothermal turbulent two- and threedimensional dispersion was extended to the case of an array of evaporating biofuel droplets. The droplet diameter, temperature and mass fraction distributions were found to be strongly dependent on the fuels used. Rapeseed Methyl Esters exhibit similar evaporating characteristics to DF-2, which indicates that it can be successfully used as an alternative fuel

Fuel n-Heptane

Droplets

Crossflow velocity, Wcrossflow

Crossflow temperature, Tcrossflow

Temperature of the walls, Twalls

Droplet injection velocity, Vp

Droplet injection temperature,

Ambient pressure

**4. Conclusion** 

1 bar 101 350Pa

Table 5. Summary of test conditions.

Tp


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