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未来世界范围内的船舶和机车废气排放法规要求大幅减少废气中的有害物(尤其是氮氧化物)的排放量。大幅减少尾气排放,同时保持低的燃油消耗也是目前重型发动机和工业用发动机的开发重点。根据从这些开发工作中获得的经验,可以得出结论:严格的排放限值标准不能仅通过一个技术阶段(发动机机内措施/安装排气后处理净化系统)来实现,而必须开发一整套经济有效的手段,其中包括降低发动机本身输出的排放值,辅之以满足要求的高效排气后处理措施。关于氮氧化物的减排,在重型发动机和工业用发动机领域,当前主要是研究和采用SCR(选择性催化还原)技术。虽然船舶和机车发动机与公路用重型发动机和较小的工业用发动机在具体要求和边界条件方面有显著不同,但是已经取得的经验(尤其是在公路应用领域)仍可用于未来船舶和机车低排放方案开发。在本文第一部分,将对船舶和机车发动机在排放法规和典型运用边界条件方面与公路用重型发动机和小型工业用发动机进行比较。进一步指出公路用重型和工业用小型发动机应用领域的新技术和发展趋势,包括基本发动机减排方案(EGR、增压、喷油系统等)、后处理技术(柴油机氧化催化器、SCR、主动/被动式柴油机颗粒过滤器、颗粒物氧化催化器等)以及传感器和控制技术。在此基础上,提出适用于船舶和机车应用的技术方案,对于这类应用场合,将考虑具体的边界条件(例如:法规要求、燃油品质及具体运行模式)。将来把基本发动机与后处理措施结合起来,将会明显增大系统布置和校准方面的难度和工作量。尤其是大型船舶和机车发动机,在最终应用之前对大量金属部件变体进行试验将会受到很大的限制。在这方面,高效开发工具(诸如后处理系统的详细一维模拟,在综合气体试验台上确定催化剂的特性,根据模拟对控制方案和传感器方案进行评估)以及针对公路应用开发的高效标准程序,都可以用来提供可靠的系统布置和校准,同时又可保持短的开发周期和发动机试验时间。
Future worldwide ship and locomotive emissions regulations require substantial reductions in the emissions of harmful emissions, especially nitrogen oxides, from exhaust gases. Significant reductions in exhaust emissions while maintaining low fuel consumption are also the current priorities for the development of heavy-duty and industrial engines. Based on the experience gained from these developments, it can be concluded that stringent emission limits can not be achieved by just one technical phase (in-engine measures / installation of an exhaust aftertreatment decontamination system) and that a whole set of economies must be developed Effective means, including reducing the emissions output of the engine itself, supplemented by efficient exhaust aftertreatment measures to meet the requirements. Regarding the reduction of nitrogen oxides, SCR (Selective Catalytic Reduction) technology is mainly researched and adopted in the fields of heavy-duty engines and industrial engines. While ship and locomotive engines differ significantly in their specific requirements and boundary conditions from those used in road heavy duty engines and smaller industrial engines, the experience already gained, especially in road applications, can still be used in future ship and locomotive low emissions Program development. In the first part of this paper, we compare ship and locomotive engines with heavy-duty and off-highway engines for emissions regulations and typical application boundary conditions. The paper also points out new technologies and development trends in the field of heavy duty and industrial small engines for highway, including basic engine emission reduction programs (EGR, pressurization, fuel injection system, etc.), post treatment technologies (diesel oxidation catalyst, SCR, Passive Diesel Particulate Filters, Particulate Oxidation Catalysts, etc.) as well as sensors and control technology. On this basis, technical solutions are proposed for ship and locomotive applications where specific boundary conditions (eg regulatory requirements, fuel quality and specific operating modes) are to be considered. Combining the basic engine with the after-treatment measures in the future will significantly increase the difficulty and workload in system layout and calibration. In large ships and locomotive engines, in particular, testing a large number of metal part variants prior to final application will be severely limited. In this regard, efficient development tools such as detailed one-dimensional simulations of aftertreatment systems, characterization of catalysts on integrated gas test rigs, evaluation of control and sensor schemes according to simulations, and efficient standard procedures developed for road applications, Can be used to provide reliable system layout and calibration while maintaining a short development cycle and engine test time.