舰船用超高增压柴油机的顾氏系统研究

针对柴油机超高增压后存在的机械负荷、热负荷过高及低工况供气不足等问题，本文以一超高增压舰船用柴油机为例，进行了顾氏系统、相继增压系统、高工况放气系统及几种常规增压系统的性能对比。结果表明，顾氏系统能降低柴油机机械负荷、热负荷、燃油消耗率及NOx排放量，改善低工况性能，与相继增压结合可进一步降低NOx排放量，提高Pme，拓宽柴油机运行范围。文中通过性能优化确定了顾氏系统正时规律，从中还得出了其控制中的最低调节工况概念，据此完成了顾氏系统控制机构的优化设计，并就系统动力学效应及其对柴油机换气特性的影响进行了讨论。

Study on Gu-system for Superturbocharged Marine Diesel Engines

By approaching such problems as insufficient air supply as well as excessively high mechanical and thermal loads lying in superturbocharged diesel engines, and taking for example a superturbocharged marine diesel engine, a performance comparison has been conducted among Gu-system, sequential turbocharging system, waste-gate system and several conventional supercharging systems. The result has shown that Gu-system can be used to reduce mechanical load, thermal load, SFC and NOx, to improve engine performance at low load and, if combined with a sequential turbocharging, to provide further reduction of NOx, improvement of Pme and extention of engine operating range. The timing law of Gu-system has been determined through optimization, whereby to leach the concept of the necessarily adjusted minimum load in its control process, and to accomplish the optimal design of Gu-system's control mechanism accordingly. The influence of the system's dynamic effect on engine scavenging characteristic has also been discussed.