MEASUREMENT OF LIQUID AND VAPOR PENETRATION OF EVAPORATING METHANOL SPRAYS

The objective of this study is to investigate spray characteristics such as liquid penetration and vapor penetration of methanol sprays under evaporative conditions. The spray characteristics were measured in an optically accessible constant volume chamber filled with nitrogen at pressures and temperatures of relevance to engine conditions. Injection pressures of 200 bar, 300 bar, 400 bar, and 480 bar were investigated. Mie-scattering and shadowgraphy techniques were used to measure liquid penetration and vapor penetration, respectively. The results show that ambient gas density has a significant effect on both methanol liquid penetration and vapor penetration. Liquid penetration is observed to decrease by 30% when ambient gas density is approximately doubled. The injection pressure has no significant effect on liquid penetration, but has a notable effect on vapor penetration. Increase in ambient gas temperature is observed to significantly reduce methanol liquid penetration, however it has only a limited influence on vapor penetration. Approximately a 13% reduction in liquid length is observed for a rise of ambient gas temperature by 35%. The present study provides data on liquid penetration and vapor penetration of methanol sprays at engine-relevant conditions along with the effect of parametric variations in ambient gas density, ambient gas temperature, and injection pressure. This data also serves to facilitate elaborate validation of computational spray models of methanol.