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

Xiaowei Wang,Hailiang Lao,Tao Gao,Tengteng Li,Chuanqi Wang,F Yan,Y Long,M Li,X Hou

doi:10.1051/e3sconf/202126801020

Abstract

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.

Highlights

The fast-growing Chinese automobile industry has become one of the pillars of China's economy
The engine operating conditions are composed of transient cycle (CHTC) and steady state operating cycle (CHSC)
In order to study the cycle difference between GB 17691-2018 standard and China automotive driving conditions of heavy-duty vehicles, this paper runs the above steady state and transient cycles on a diesel engine, compares and analyzes emission differences under above cycles

Summary

Introduction

The fast-growing Chinese automobile industry has become one of the pillars of China's economy. In the "China Motor Vehicle Environmental Management Annual Report (2018)", diesel trucks only accounts for 7.8% of automotive ownership, emitting 57.3% of nitrogen oxides and 77.8% of particulate matter [1]. The GB 17691-2018 "Limits and measurement methods for emissions from diesel fuelled heavy-duty vehicles" (China VI) issued in 2018 adopts the world harmonised transient cycle (WHTC) and the world harmonised steady state cycle (WHSC) for type certification [2]. In the development process of the above operating conditions, the actual driving data were mostly from European and American countries rather than China. In order to study the cycle difference between GB 17691-2018 standard and China automotive driving conditions of heavy-duty vehicles, this paper runs the above steady state and transient cycles on a diesel engine, compares and analyzes emission differences under above cycles

Engine and equipment

Comparison of CHSC and WHSC

Comparison of CHTC and WHTC

Conclusions