Effect of Single and Double-Deck Pre-Chamber Designs to the Combustion Characteristics of Premixed CH ₄  /Air

An experiment was carried out to investigate the effect of single and double-deck pre-chamber on the combustion characteristics of premixed CH₄/air in a constant volume vessel using schlieren method. A special design was proposed for the visualization of the pre-chamber. Combustion with different initial temperatures (300 K, 400 K, 500 K) were observed at stoichiometric ratio to lean-burn limit. Although single-deck pre-chamber has advantages over double-deck pre-chamber in both initial flame development duration and main combustion duration, the latter could extend the lean-burn limit by up to 0.3 and promote the stability of ignition. It is also found that extensive distribution of active species in main chamber before ignition can accelerate speed of flame propagation enormously.