Real Emissions Test Bench: Transient emission/consumption measurement for low-emission powertrains

车辆推进系统研究所(LAF)，由博士-ing教授领导。凯撒斯劳滕技术大学的Michael Günthner打算在一个瞬时发动机试验台上配备一个快速采样的排放和油耗测量系统。特别是，这个系统应该能够测量所谓的二次排放成分(目前还不受排放法规的限制)。该系统将被用来研究在不同程度的混合动力的实际驾驶情况下，替代燃料在瞬时负荷循环中的排放和油耗影响。该系统包括气体废气成分和微粒排放的测量装置，以及联合燃料调节和测量单元。在研究相关的现有和未来替代燃料时，选择了能够解决发动机瞬时运行过程中的动态过程的测量规范。废气测量系统基于傅里叶变换红外光谱仪(FTIR)，它能够通过吸收红外辐射光谱来检测和定量多种预定义的气体混合物成分。此外，还将使用独立的气体分析仪来检测废气中的总烃(THC)和氧气浓度以及进口空气中的二氧化碳(用于确定废气再循环率)。排气颗粒物排放将在颗粒分级仪中进行分类，颗粒分级仪对纳米范围内的颗粒进行电荷充电，并通过电子迁移率和充电值测量颗粒的大小和数量。测量系统由燃料调节和测量相结合的单元完成。该装置将供应给试验台的燃料调节到预定的压力和温度水平，并永久监控燃料的质量流量。醇和特殊含氧物等新型燃料要求系统配备特别耐腐蚀的密封和管道材料。

The Institute of vehicle propulsion systems (LAF), led by Prof. Dr.-Ing. Michael Günthner at the Technical University of Kaiserslautern, intends to equip a transient engine testbench with a fast-sampling emission and fuel consumption measurement system. In particular, this system should be capable of measuring so-called secondary exhaust emission components (which are currently not yet subject to emission regulations). The system will be used for investigating emission and fuel consumption effects of alternative fuels in transient load cycles as occurring in real driving situations at varying levels of hybridisation.The system includes measurement devices for gaseous exhaust components and particulate emissions as well as a combined fuel conditioning and measurement unit. The specifications have been chosen for the measurement to be able to resolve dynamic processes during transient engine operation when investigating relevant present and future alternative fuels. Special emphasis is on renewable fuels and measured variables which are particularly relevant in the development of special combustion systems adapted to such fuels.The exhaust gas measurement system is based on a Fourier Transformation Infrared Spectrometer (FTIR), which is able to detect and quantify multiple predefined components of gas mixtures spectrally by absorption of infrared radiation. In addition, separate gas analysers to detect the total hydrocarbon (THC) and oxygen concentration in the exhaust gas as well as carbon dioxide in the inlet air (for determining the exhaust gas recirculation rate) will be used.Exhaust particulate emissions will be classified in a particle sizer, which electrically charges particles in the nm-range and measures their size and number through the electrical mobility and charge values.The measurement system is completed by a combined fuel conditioning and measurement unit. This unit conditions the fuel supplied to the test bench to predefined pressure and temperature levels and permanently monitors the mass flow of the fuel. New types of fuels like alcohols and special oxygenates require the system to be equipped with particularly resistant sealing and piping materials.