Summary: | 碩士 === 朝陽科技大學 === 環境工程與管理系 === 103 === This study adapted the procedure proposed by ISO GUM and Taiwan Accreditation Foundation to evaluate the measurement uncertainty of emission gases from motorcycles. The uncertainties of factors including gas analyzer correction and sampling were evaluated. According to the procedure of ISO GUM measuring guides, type A evaluation on exhaust detection of motor vehicles was used to obtain the data of the standard vehicle and calculating with variances. The results of this study show that the emission of cold start test is significantly higher than hot start test, indicating that the measurement under different start mode (hot vs. cold) would affect the measurement accuracy. The effect of the position of the sampling probe was also evaluated in this study. Three positions (60 cm, 40 cm and 20 cm depth from the exhaust pipe) were compared. The result show that the concentration is higher while the probe is set in the deeper position, which indicate that the probe position would affect the measurement results.
In this study, gas analyzer correction and sampling factors were considered to evaluate the measurement uncertainties of the exhaust gases. The results show that under 68% of confidence level, the measurement uncertainties are 0.03% for CO, 39.55 ppm for HC, and 0.13% for CO2. Under the 95% confidence level, if k = 2 for expansion coefficient, the expanded uncertainties are 0.06% for CO, 79.11 ppm for HC, and 0.27% for CO2.
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