Variable compression ratio range extender optimised for heavy duty vehicles with renewable fuels

这个为期12个月的项目将开发和演示一种可变压缩比增程器发动机，该发动机针对使用可再生燃料的重型车辆进行优化，其基础是在第一阶段成功完成的可行性研究演示的结果。在第一阶段，与潜在未来客户的讨论确定了对性能验证原型发动机的需求，这是Libertine“intelliGEN”反相自由活塞开发平台商业化道路上的下一个关键里程碑。在第二阶段，性能验证发动机将集成Libertine的“intelliGEN”平台和分包商马勒动力系统的MJI被动预燃室内燃系统，并将在热管理、耐用性和电力转换效率方面实施多项增强，以延长测试运行时间，并根据客户要求规范验证性能。Libertine的“intelliGEN”反向自由活塞开发发动机系统为原始设备制造商开发充分利用可再生低碳燃料的新产品提供了手段。这些产品对于“难以电气化”的运输应用的脱碳至关重要，包括重型商用车，重型非公路车辆，以及部分轻型商用车和乘用车领域，其中车辆使用和充电限制是电气化的障碍，以及更大范围的分布式发电应用。自由活塞发动机的可变压缩比和非正弦活塞运动能力，由于这些新燃料的燃烧特性，有可能使可再生生物燃料和合成低碳“电子燃料”更清洁、更有效地使用。特别是，生物乙醇等可再生酒精燃料具有很高的汽化热，虽然通常清洁燃烧，有害排放物比汽油少，但由于冷室表面未汽化的燃料（“壁湿”）导致持续熄火，在冷启动时可能会产生更多的碳氢化合物排放。第一阶段表明，在冷启动操作的最初几秒钟内，通过提高压缩比来补偿空气/燃料混合物的热量损失，可以减少这种负面影响。到2050年，许多在2030年售出的新商用车仍将在英国和全球范围内行驶。因此，为了实现2050年实现净零排放的目标，至关重要的是，到2030年销售的大多数商用车都必须在这些旅程和充电尚不经济、实用或方便的用例中兼容净零碳燃料。

The proposed 12 month project will develop and demonstrate a variable compression ratio range extender engine optimised for heavy duty vehicles with renewable fuels, building on findings from the successful feasibility study demonstration completed in Phase 1\.In Phase 1, discussions with potential future customers identified the need for a performance validation prototype engine as the next key milestone on the path to commercialisation of Libertine's 'intelliGEN' Opposed Free Piston development platform. In Phase 2 a performance validation engine will integrate Libertine's 'intelliGEN' platform with subcontractor MAHLE Powertrain's MJI passive pre-chamber internal combustion systems, and will implement multiple enhancements for thermal management, durability and electrical power conversion efficiency in order to achieve extended test operating durations and validate performance against customer requirement specifications.Libertine's 'intelliGEN' Opposed Free Piston development engine systems provide the means for OEMs to develop new products making full use of renewable low carbon fuels. These products will be essential for the decarbonisation of 'hard to electrify' transport applications including heavy duty commercial vehicles, heavy duty off-highway vehicles, for a proportion of light duty commercial vehicle and passenger automotive segments where vehicle use and recharging constraints are a barrier to electrification, and for a larger range of distributed power generation applications.The variable compression ratio and non-sinusoidal piston motion capabilities of Free Piston Engines have the potential to enable cleaner and more efficient use of renewable biofuels and synthetic low carbon 'e-fuels' owing to the combustion characteristics of these new fuels. In particular, renewable alcohol fuels such as bioethanol have a high heat of vaporisation and whilst generally clean burning, with fewer harmful emission than gasoline, can produce increased hydrocarbon emissions at cold start due to un-vaporised fuel on cold chamber surfaces ('wall wetting') resulting in persistent misfiring. Phase 1 demonstrated that this negative impact can be reduced using an elevated compression ratio during the first few seconds of cold-start operation to compensate for heat loss from the air/fuel mixture.Many of the new commercial vehicles sold in 2030 will still be on the roads in the UK and worldwide by 2050\. To meet the objectives for net-zero transport in 2050, it is therefore essential that the majority of commercial vehicles sold in 2030 are compatible with net zero carbon fuels for those journeys, and use cases, where recharging is not yet economic, practical or convenient.