Effect of Brown’s gas addition on combustion and emissions of homogeneous charge compression ignition engine

ABSTRACT

The oxides of nitrogen (NO_x) and smoke emitted by widely used compression ignition (CI) engines of automobiles are among the major contributor to the environmental pollution. Several attempts are being made to reduce these exhaust emissions from automobiles. Low-temperature combustion (LTC) with homogeneous charge compression ignition (HCCI) is one of the strategies to reduce these engine exhaust emissions. The present work investigates the addition of Brown’s gas (HHO) in the intake manifold of a stationary common rail direct injection CI engine in HCCI mode. In the experiments, electronically assisted fuel injection system was used to maintain the injection pressure to 250 bars. The effect of HHO addition on the combustion and emissions was studied for different loads and injection advance. It was observed that the brake power, brake thermal efficiency, and brake-specific fuel consumption were improved by around 5% due to HHO addition. However, they were found to be decreased with increased injection advance. Moreover, a considerable reduction in NO_x emission, i.e., 1–12 ppm was recorded for early injection mode. Thus, Brown’s gas addition with LTC strategy may result in reduced environmental pollution.

KEYWORDS:

• Brown’s gas (HHO gas)
• combustion
• early direct injection HCCI engine
• emission
• nitrogen oxides (NO_x)
• water electrolysis