低温环境汽油机颗粒捕集器再生间隔里程评估方法

对汽油机颗粒捕集器（gasoline particulate filter，GPF）碳载量估算的温度修正方法，以及低温环境下的GPF再生间隔里程进行研究。利用发动机台架试验测量了GPF颗粒物再生反应速率，通过对数作图法拟合反应速率得到再生反应活化能，氧和颗粒物的反应活化能为81.6~91.4 kJ/mol，二氧化碳和颗粒物的反应活化能为159.2~218.9 kJ/mol。基于反应活化能计算了不同环境温度下颗粒物再生反应速率的修正系数；测量试验车低温冷启动阶段颗粒物累积速度，计算颗粒物排放的温度修正系数。以轻型车排放国六标准I型试验为基础，利用颗粒物再生反应速率和排放的温度修正系数对低温环境下GPF主动再生间隔里程进行了仿真。与寒区道路试验中获得的实际GPF颗粒物累积数据对比，仿真结果能较为准确地预测GPF在寒区不同工况下的颗粒物累积速度。试验和仿真结果均显示车辆低速行驶时GPF内颗粒物累积速度更易受低温环境影响。

Evaluation method of gasoline particulate filter regeneration interval mileage in a low-temperature environment

The gasoline particulate filter (GPF) regeneration interval mileage in a low-temperature environment was studied based on a temperature correction method for GPF soot load estimation.The GPF soot regeneration action rate was measured by the engine dyno test, and the activation energy of the regeneration reaction was obtained by the logarithm method and the line fitting method. It was shown that the activation energy of oxygen and soot was 81.6-91.4 kJ/mol, and that of carbon dioxide and soot was 159.2-218.9 kJ/mol. The activation energy was then used to calculate the correction coefficients for the soot regeneration action rate in variant environment temperatures. The accumulated velocity of the soots in the cold start stage of the test vehicle was measured, and the correction coefficients for soot emission in a low-temperature environment were acquired. Based on the type I test of CHINA 6 for light-duty vehicle emission, GPF active regeneration interval mileage in a low-temperature environment was simulated by applying the temperature correction coefficient of soot emissions and regeneration rate. Compared with GPF soot accumulation data from test vehicles driving on road in cold region, the simulation result had enough precision to predict GPF soot load accumulation rate for vehicle usage under different working conditions in cold region. Both the simulation and test results indicated that GPF soot accumulation rate was easily affected by low temperature when the vehicle running at low speed.