Energy efficiency analysis of multi-event injections

为了满足当前和未来的柴油发动机排放标准，有必要能够全面控制发动机的运行，将燃料注入发动机的方法（喷射技术）和任何排气后处理装置。作为这一总体要求的一部分，这项研究将集中在加油和加油控制的方法如何影响发动机的性能和排放。多脉冲喷射技术已被认为是减少氮氧化物和颗粒物排放的有效途径。然而，与低氮氧化物和低PM要求相关的热释放率导致偏离发动机条件，通常最大化燃烧过程的能源效率。有必要以有效的方式平衡排放和能源使用效率。因此，主要目的是建立一个分析模型来评估现代柴油机的多脉冲燃油喷射性能。为了校准和验证该模型，将在一台原型共轨柴油发动机上进行经验检验，该发动机由基于现场可编程门阵列（FPGA）的复杂系统控制，该系统集成了嵌入式控制器和复杂的可编程电源驱动器。气缸气体压力、温度和成分的详细时间剖面将通过气缸压力传感器、快速响应温度传感器和气缸内直接气体采样分析仪进行测量。通过这种方式，当以超低排放燃烧为目标时，将有可能研究能源效率与燃油喷射计划之间的基本权衡。

To meet the current and future emissions standards for Diesel Engines it is necessary to able to electonically control in an holistic manner the operation of the engine, the methods of getting the fuel into the engine (injection techniques) and any exhaust aftertreatment device. As part of this overall requirement this research will concentrate on how the methods of fuelling and fuelling control effects the engine performance and emissions. The technique of multi-pulse injection has been identified as an effective way to reduce nitrogen oxides (NOx) and particulate matter (PM) emissions. However, the heat release rates associated with low NOx and low PM requirments cause departures from engine conditions which normally maximize the energy efficiency of the combustion process. There is a need to balance in an effective manner emissions with energy-use efficency. Thus, the main aim will be to develop an analytic model to assess the performance of multi-pulse fuel injection in modern diesel engines. To calibrate and validate this model the transient thermal and combustion characteristics of the engine cycle will be examined empirically on a prototype common-rail diesel engine controlled by a sophisticated a field programmable gate array (FPGA) based system integrated with an embedded controller and a sophisticated programmable power drive. The detailed temporal profiles of cylinder gas pressure, temperature, and composition will be measured with cylinder pressure transducers, fast-response temperature sensors, and in-cylinder direct gas sampling analyzers. In this way it will be possible to investigate the fundamental trade-offs of the energy efficiency versus the fuel injection schedule when ultra low emission combustion is targeted.