FKFS和IFS氢能车辆驱动系统研究

The Investigation of Hydrogen-Based Vehicle Propulsion Systems at FKFS and IFS

摘要:

本文介绍氢气在交通运输领域的相关应用，以氢气直喷（H₂-DI）内燃机的开发过程为例，阐述斯图加特汽车工程与车辆发动机研究所（FKFS）和斯图加特大学汽车工程学院（IFS）的研究工作。在单缸乘用车发动机试验台上研究氢气高压直喷特性（FVV项目），目标是实现氢气发动机在当量混合条件下稳定运行，从而以较低的增压需求输出较大功率。当发动机在高负荷条件下工作时，当量混合比更容易导致爆震现象。为了防止末端气体发生预反应，喷射氢气将在点火上止点（TDCF）前不久开始，随后由火花塞点燃。喷射持续时间以及喷射的最大质量流量都将在不同程度上影响燃烧的持续时间。此外，本研究还探讨了氢气燃烧过程中所存在的问题，如较高的氮氧化合物排放量，以及未燃氢气进入排气系统等。

Abstract:

The defossilisation of transport is of central importance for meeting global climate targets. In addition to introducing battery-electric vehicles that today are mainly intended for individual and local passenger transport， fuels based on renewable resources offer the possibility of fulfilling energy-intensive transport tasks with low global greenhouse gas emissions. Hydrogen produced from renewable energy is gaining particular importance here， as its use in mobile applications ensures not only overall low global warming potential but also the lowest tailpipe greenhouse gas emissions.In this paper， the various aspects of the use of hydrogen in vehicles are briefly presented and the work at FKFS and IFS is illustrated using the development of an H₂-DI combustion process for ICE applications as an example.The presented FVV research project investigates a high-pressure direct injection concept on a single-cylinder passenger car engine test bench. It aims to operate a spark-ignited engine near stoichiometric conditions to produce a significant power output with low boost pressure demand. However， for a hydrogen engine， a stoichiometric mixture leads to an increased knocking tendency towards higher loads. To avoid pre-reactions in the end gas， the injection starts shortly before TDCF and the hydrogen jet is ignited by the spark plug. The injection duration and therefore the maximum hydrogen mass flow through the injector nozzle influence the combustion duration. Challenges of the investigated hydrogen combustion process are， among others， the higher NO_X emission level compared to the lean operation and the hydrogen slip into the exhaust system.