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

车辆推进系统研究所（LAF），由教授博士领导- Ing.凯撒大帝技术大学的Michael Günthner打算为瞬态发动机试验台配备快速采样排放和油耗测量系统。特别是，该系统应该能够测量所谓的二次废气排放成分（目前尚未受到排放法规的约束）。该系统将用于研究在不同混合动力水平下，在真实的驾驶情况下，在瞬态负载循环中替代燃料的排放和燃料消耗影响。该系统包括用于测量气体排气成分和颗粒排放的测量装置，以及组合燃料调节和测量单元。在调查相关的当前和未来替代燃料时，选择测量的规格是为了能够解决瞬态发动机运行期间的动态过程。特别强调的是可再生燃料和测量变量，这些变量与开发适用于此类燃料的特殊燃烧系统特别相关。废气测量系统基于傅里叶变换红外光谱仪（FTIR），能够通过红外辐射吸收光谱检测和量化气体混合物的多种预定义成分。此外，单独的气体分析仪可检测废气中的总碳氢化合物（THC）和氧气浓度以及进气中的二氧化碳浓度（用于确定废气再循环率）。废气颗粒物排放将在粒度仪中进行分类，使纳米粒子带电，测量范围，并通过电迁移率和电荷值测量它们的大小和数量。测量系统由组合的燃料调节和测量单元组成。该装置将供应到试验台的燃油调节到预定义的压力和温度水平，并永久监控燃油的质量流量。酒精和特殊含氧化合物等新型燃料要求系统配备特别耐用的密封和管道材料。

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.