Effects of operating parameters on steady and transient behaviors of a closed cycle diesel engine

This study set out to develop the first closed cycle diesel engine (CCDE) system in Taiwan and to study the engine performance under transient and steady operation conditions. The aim of the development was to design and establish these systems, including a cooling system, a CO2 absorbing system, a charge mixing system and an oxygen control system. The exhaust emissions CO2 and smoke from the engine were measured and analyzed using different chemical absorbents (KOH, NaOH and Ca(OH)2) in the CO2 absorbing system under different injection pressures (155 kg/cm2, 185 kg/cm2 and 200 kg/cm2) and different electric powers (1 kW, 2 kW and 4 kW).KOH was found to have the best effect on the absorption of CO2 among the three absorptive liquids (KOH, NaOH and Ca(OH)2), and it achieved the lowest oscillation of oxygen at a lower electric load. The brake specific fuel consumption (bsfc) with KOH used in the CO2 absorber was less than that for the two other absorbents. It was found that with increasing injection pressure, the concentration of smoke decreased but both CO2 concentration and bsfc increased. The concentration of smoke increased, but the bsfc decreased as the electric load increased. The larger the electric load was, the longer it took before the oxygen concentration reached a steady state.