AIR-FUEL RATIO CONTOURS WITHIN A SPRAY

The work described in this paper was undertaken to obtain measurements of air-fuel ratio within evaporating liquid fuel sprays with the purp ose of providing experimental data against which spray models might be checked and established. The central idea was to sample isokineticall y within the spray using a miniature cyclone probe which separates the fuel droplets and channels the gas phase mixture of air and evporated fuel to an analyser. The apparatus consisted of a Tyne engine combust ion can serving as a preheater for the working fluid supplied from a c ompressor plant, the spray rig in which a hollow cone spray was used, the sampling cyclone probe of 10 mm diameter and a chromatographic air -fuel ratio analysis unit. Air-fuel ratio contours within a spray of k nown characteristics for three operating conditions were obtained and are presented. These results are the first of their kind and should pr ove useful in checking and establishing mathematical models of spray m ixing and evaporation. (C) 1997 Elsevier Science Ltd.