Affiliations: Department of Environmental Science and Engineering,
Tsinghua University, Beijing 100084, China | CECERT, University of California at Riverside, CA
92507, USA
Abstract: The dynamometer tests with different driving cycles and the
real-world tests are presented. Results indicated the pollutants emission
factors and fuel consumption factor with ECE15 + EUDC driving cycle
usually take the lowest value and with real world driving cycle occur the
highest value, and different driving cycles will lead to significantly
different vehicle emission factors with the same vehicle. Relative to the ECE15
+ EUDC driving cycle, the increasing rate of pollutant emission factors of
CO, NOx and HC are −0.42–2.99, −0.32–0.81 and
−0.11–11 with FTP75 testing, 0.11–1.29, −
0.77–0.64 and 0.47–10.50 with Beijing 1997 testing and
0.25–1.83, 0.09–0.75 and − 0.58–1.50 with real world
testing. Compared to the carburetor vehicles, the retrofit and MPI + TWC
vehicles' pollution emission factors decrease with different degree. The
retrofit vehicle (Santana) will reduce 4.44%–58.44% CO, −
4.95%–36.79% NOx, − 32.32%–33.89% HC, and −
9.39%–14.29% fuel consumption, and especially that the MPI + TWC
vehicle will decrease CO by 82.48%–91.76%, NOx by 44.87%–92.79%, HC
by 90.00%–93.89% and fuel consumption by 5.44%–0.55%. Vehicles can
cause pollution at a very high rate when operated in high power modes; however,
they may not often operate in these high power modes. In analyzing vehicle
emissions, it describes the fraction of time that vehicles operate in various
power modes. In Beijing, vehicles spend 90% of their operation in low power
modes or decelerating.
Keywords: real-world testing, vehicle emission factors, driving cycle, power modes
