Study on ignition quality improvement of LPG (part 1) evaluation of ignition quality of LPG with cetane number improving agents

The objective of this study is to improve the ignition quality of LPG in or der to utilize LPG as diesel fuel. First, the relationship between the ceta ne numbers and ignition delay periods of primary standard fuels (mixtures o f n-cetane and heptamethylnonane) and diesel fuels was investigated by meas uring the ignition delay periods using a constant volume combustion chamber . A good relationship between the cetane numbers and ignition delay periods under the conditions of combustion chamber temperature of 550 degreesC and pressure of 4 MPa. Consequently, a cetane number estimation function could be established. Next, the constant volume combustion chamber was modified to evaluate the ignition delay period of LPG with cetane number improving a gents and these cetane numbers were estimated. The estimated cetane numbers of LPG with cetane number improving agents agreed with those calculated us ing the results of the diesel engine study. The estimated cetane numbers of LPG with 15 wt% cetane number improving agents were greater than 45 sugges ting that LPG can be used as diesel fuel.