Microscopic spray characteristics of diethyl ether–diesel blends under single and split injection strategies

Abstract

The phase doppler interferometry technique was used to thoroughly investigate microscopic spray characteristics of single and split injection strategies. The diethyl ether blending with diesel resulted in smaller and uniform droplet formation. Diethyl ether–diesel blend spray exhibited a lower droplet axial velocity distribution than baseline diesel, which can be improved by split injection strategies. At atmospheric pressure, the maximum axial velocity for diesel and diethyl ether–diesel blends was almost identical under single and split injection strategies. However, split injection improved the spray droplet's axial velocity at higher ambient pressures compared to single injection. The chances of coalescence and having coarse droplets were higher at elevated ambient pressure, especially for lower fuel injection pressures. Therefore, increasing the fuel injection pressure is more suitable to avoid droplet coalescence. Unlike the split ratio, dwell time strongly influenced fuel spray atomization. The droplet diameter distribution exhibited a higher probability of finer droplets for a longer dwell time of 0.45 ms than a shorter dwell time of 0.15 ms. A major finding of this study is that diethyl ether–diesel blend spray with a longer dwell time exhibited superior spray characteristics.