Turbo-Discharging: Reducing CO2 Emissions from Current and Future Vehicles

涡轮排气是利用内燃(IC)发动机空气系统来提高燃油经济性、减少发动机二氧化碳排放、同时增加发动机扭矩的一种全新方法。利用一种新的分流排气装置，排污流和相关能量通常作为排气流的一部分被涡轮回收。在主位移流过程中，涡轮被绕过，曲轴不需要做任何工作来排出通过涡轮的燃烧气体。其结果是回收排污能量，而不会对发动机曲轴扭矩产生负面影响。然后，这些能量被创新地用于为排气系统降压，排气系统在排气冲程期间产生额外的曲轴扭矩，从而增加主要扭矩并减少二氧化碳排放。第二个好处包括提高排污脉冲的能量利用率，并可能改善低速扭矩(通过增加涡轮的压降)。汽缸内残留的热废气将减少，这将延长涡轮增压火花点火发动机的爆震极限，允许比目前可能的尺寸进一步缩小。重要的是，对燃烧系统的影响可以忽略不计，允许涡轮排放方法用于所有现有和未来的内燃机，而无需进行重大重新设计。因此，对二氧化碳排放的影响可能比仅在小规模利基市场提供更大二氧化碳减排的昂贵技术大得多。涡轮排放需要增加涡轮和压缩机(如传统涡轮增压系统中使用的那样)，并且不需要复杂的设备，如废物处理或可变几何涡轮。因此，成本很低，使该技术与许多其他二氧化碳减排技术相比处于非常有竞争力的地位。随着发动机制造商需要组合技术来满足未来的二氧化碳排放目标，这项技术将对行业非常有吸引力。与工业界的初步接触表明，在他们进行投资之前，需要对这项技术进行实验演示。该项目将通过实验研究、开发和演示涡轮放电作为一种可行的、经济高效的减少内燃机二氧化碳排放的新方法，最终导致行业合作和车载涡轮放电的实施。

Turbo-Discharging is a fundamentally new approach to using internal combustion (IC) engine air systems to improve fuel economy, reduce engine CO2 emissions and simultaneously increase engine torque. Using a novel divided exhaust flow arrangement, the blow-down flow and the associated energy usually lost as part of the exhaust flow is recovered by a turbine. During the main displacement flow the turbine is by-passed and the crankshaft does not have to do any work exhausting the burnt gases through the turbine. The result is the recovery of the blowdown energy without negatively impacting the engine crankshaft torque. This energy is then innovatively used to depressurise the exhaust system which generates extra crankshaft torque during the exhaust stroke giving a primary torque increase and CO2 emission reduction.Secondary benefits include increased energy availability from the blowdown pulse and potentially improved low speed torque (through increased pressure drop across the turbine). There will be less hot exhaust gas residuals within the cylinder which will extend the knock limit of turbocharged spark ignition engines allowing further downsizing than is currently possible.Importantly, the effect on the combustion system is negligible allowing the Turbo-Discharging approach to be used with all current and future IC engines without significant redesign. The impact on CO2 emissions could therefore be much larger than costly technologies offering larger CO2 reductions in only small niche markets.Turbo-Discharging requires the addition of a turbine and compressor (as used in a conventional turbocharging system) and does not require complexities such as wastegating or variable geometry turbines. The cost is therefore small, placing the technology in a very competitive position compared with many other CO2 reducing technologies. With engine manufacturers requiring combined technologies to meet future CO2 emission targets, this technology will be very attractive to industry. Initial contact with industrial has shown that experimental demonstration of this technology is needed before they will invest. This project will experimentally study, develop and demonstrate Turbo-Discharging as a feasible, cost effective and novel approach to reducing IC engine CO2 emissions, ultimately leading to industrial collaboration and implementation of Turbo-Discharging on-vehicle.