Affiliation:
1. Clemson University, Greenville, SC
2. University of Michigan, Ann Arbor, MI
Abstract
Stringent engine emission regulations highlight the importance of proper engine control during transient operation. In recent years, fast emissions analyzers that measure CO and CO2 simultaneously have allowed for fast air-to-fuel ratio (AFR) calculation under steady-state engine operation. However, using a steady-state methodology to calculate AFR under transient conditions can lead to significant data interpretation errors. This research introduces an experimental cycle-by-cycle AFR calculation routine developed for transient operation using cycle-resolved CO2 and CO analyzers. Need for the new technique arises when the composition of recycled exhaust gases vary significantly from expected post-combustion products corresponding to the true in-cylinder AFR. This condition commonly occurs when AFR is changed from one cycle to the next. The peak difference between the new method and traditional methods is demonstrated to be in the range of 0.1 relative air-to-fuel ratio points, or approximately 10%. These results are for low dilution conditions where the new method should show minimal difference as compared to traditional methods. If residual gas fraction levels were increased the difference in corrected to uncorrected results would become even greater, motivating the use of the new method in high-dilution engines.
Publisher
American Society of Mechanical Engineers
Cited by
1 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献
1. In-Cylinder CO2 Sampling Using Skip-Firing Method;Journal of Engineering for Gas Turbines and Power;2019-04-25