Particulate Matter Emission Characteristics under Transient Pattern Drivings

Real-time and simultaneous measurements of particulate matter emissions (PME) under transient engine operating conditions have been carried out by several methods under 20 kinds of actual speed pattern driving schedules, and frequencies of each engine speed and load zone used for individual driving schedules at different laden weight are statistically analysed. On the other hand, PME are also estimated and compared with PME characteristics under steady engine operations. Applying these data, technical possibilities to replace comprehensive driving conditions of actual speed patterns with series of steady engine operating conditions and to obtain equivalent PME are studied. As a result of the study, it has been verified through the experiments that the three-point steady-state operations can yield nearly identical PME characteristics (g/test) to those of transient speed pattern operations, by using time-averaged values of the used engine speed and load.