Analysis of the engine test cycles from China VI heavy duty vehicle standard and China automotive test cycle

This paper studied the engine test cycles including world harmonized steady cycle (WHSC), world harmonized transient cycle (WHTC) , china heavy-duty steady cycle (CHSC) and china heavy-duty transient cycle (CHTC) based on a diesel engine which meet the China VI heavy duty vehicle emission standard. The results show that regression analysis of speed, torque and power all meet the requirements of the China VI heavy duty vehicle standard. For this engine, NOx, PM and THC pollutants under CHSC are 134.5%, 29.6% and 94.4% higher than those under WHSC, respectively. PN emissions of CHSC is 65.6% lower than that of WHSC. NOx, PM and PN pollutants under CHTC are 62.9%, 96.4% and 64.3% higher than those under WHTC, respectively. The exhaust temperature of the first 350 seconds at CHTC is lower, which poses a greater challenge to the conversion efficiency of the after-treatment system at low speed and low load