Characterization of double injection hydrogen jet using acetone-PLIF in a constant volume chamber

As global warming intensifies, hydrogen is recognized as a viable alternative to conventional fossil fuels thanks to its potential for clean combustion. However, the direct application of hydrogen in internal combustion engines remains challenging due to the lack of detailed knowledge in the mixture formation process. A crucial aspect is understanding the mixture distribution of hydrogen, which significantly impacts combustion efficiency and pollutant formation. This study investigates the effect of double injection on the mixing behavior of hydrogen using Planar Laser-induced Fluorescence (PLIF). Simultaneously, Schlieren imaging was carried out to validate the PLIF measurements and confirm for any slipping between the acetone and hydrogen. The imaging results demonstrated a strong correlation between the PLIF and Schlieren images, confirming that the acetone-doped PLIF effectively captures the hydrogen jet structure with minimal interference from hydrogen’s high diffusivity. These results suggest that this approach can reliably measure the qualitative distribution of the hydrogen mixture. Furthermore, the optimization of double injection parameters demonstrates the potential to form a flammable mixture near the spark plug by promoting jet area expansion.