Characterization of NH3 emissions from light-duty passenger cars

The prototype vehicle was driven on a chassis dynamometer in the light-duty vehicle test cycle (WLTC) condition, and the NH₃ emissions in the exhaust gas of the light-duty vehicle were detected by the portable emission test system (PEMS), quantum cascade laser (QCL), and Fourier transform infrared test method (FTIR) in two measurement principles; and the NH₃ emissions from the light-duty vehicle were measured by the direct sampling and the dilute sampling in two different sampling methods. emissions from light-duty vehicles were measured by two different sampling methods: direct and dilute sampling. The results show that the modal trends of the two NH₃ measurement principles are basically the same, and the peak QCL response is higher. The repeatability of the NH₃ emissions from the direct and dilute sampling tests is good, and the final results of the full-travel direct and dilute NH₃measurements do not deviate much from each other.