| Currently the air pollution problem in China is getting deteriorating day by day which is mainly caused by vehicle harmful exhausts.In order to reduce the exhausts, many kinds of exhaust control technology are becoming the core technology of the spark ignition engine especially the after-treatment ones.The three-way catalytic converter(TWC) is an effective mean to control vehicle exhaust pollution.The conversion efficiency of a new TWC can reach as high as 95%.However,the efficiency of the TWC will decrease and finally becoming aged under harsh conditions long time.According to the aforementioned situation,to establish a whole life-evaluating system to provide test data and scaling standard for the TWC has become a key technology issue earnestly.And the most pivotal aspects of the evaluating system are the TWC aging method selection and the relative test assembly.This paper analyzes the aging principle of the TWC which mainly are thermal inactivation and poisoning.Besides,this paper also does research on several main aging modes both domestically and internationally.They can be classified to two accelerated aging modes:two-phase aging and four-phase aging.The test bench configuration introduced in this paper is built according to the aging mode provided by GM Corporation which is a four-phase one.The test is run 200 hours,equaling to a 100 thousand kilometer driving realistically.The inlet temperature of the TWC can reach above 800℃during the test through adjusting the already calibrated engine. Also by second air injection,a higher temperature can be reached to accelerate the TWC aging.At last,an accelerated aging evaluating test configuration is designed and developed initially.
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