Modeling and Validation of the Oil Control Ring Performance for a Orbiting Face-Sealing

由于地面交通正在缓慢但肯定地实现电气化，航空运输业正在寻找减少碳足迹的解决方案。不幸的是，电池太重了，无法用于商业飞行，而且廉价、广泛使用的生物喷气燃料仍然是未知数。最好的解决方案仍然是提高发动机效率，以尽可能减少燃料消耗。大型燃气轮机已经达到了令人印象深刻的效率水平，但由于燃烧温度有限，加上高粘性和尖端损失，小型燃气轮机仍然相对低效。为了彻底降低燃油消耗，制造商不得不从新的角度重新审视替代发动机配置。清洁推进的主要候选者之一是非往复式内燃机类型，它结合了体积发动机的高效率，同时以其高功率密度而闻名。不幸的是，这些类型的发动机也以其油耗而闻名，在用于航空航天应用之前需要减少油耗，以满足客户的感知，重量和即将出台的排放法规。通过表面密封的油控制环（ocr）泄漏的油占总耗油量的一半以上，这是降低总耗油量的首要目标，因为它可以在不显著影响发动机耐久性的情况下大幅降低总耗油量。本项目旨在通过详细的建模和实验验证来改进发动机ocr。UdeS和P&WC团队将在之前的OCR模型的基础上，开发一种新的流体动压数值公式，为这种类型的发动机所需的轨道表面密封OCR壳体界面量身定制。然后将流体动压子模型集成到完整的OCR模拟代码中，该代码可用于预测漏油、摩擦和磨损的趋势。同时，将建立一个实验装置，通过测量具有代表性的受控环境中的油耗和油膜厚度来验证模型和OCR性能。

As ground transportation is slowly but surely being electrified, the air transportation industry is looking for solutions to reduce its carbon footprint. Unfortunately, batteries are too heavy to be viable for commercial flight and cheap, widely available bio-jet-fuel is still eluding. The best solution remains to increase engine efficiency to reduce fuel consumption as much as possible. Large gas turbines have reached impressive efficiency levels, but small gas turbines remains relatively inefficient due to limited combustion temperatures combined to high viscous and tip losses. In order to achieve radical reduction in fuel consumptions, manufacturers are forced to revisit alternative engine configurations with a new perspective. One of the prime candidates for cleaner propulsion are the non-reciprocating combustion engines types that combine high efficiencies of volumetric engines while being well-known for their high power density. Unfortunately, these type of engine are also well-known for their oil consumption that needs to be reduced before they are used for aerospace applications in order to meet customer perceptions, weight and forthcoming emission regulations. The leakage through the face-sealing Oil Control Rings (OCRs) can represent more than half of the oil consumption and is the first target to reduce total oil consumption as it can be drastically reduced from current values without a significant impact on engine durability. This proposed project aims at improving engine OCRs through detailed modeling and experimental validation. The UdeS and P&WC team will build upon previous OCR models by developing a novel numerical formulation of the hydrodynamic pressure generated tailored for the orbiting face-sealing OCR-housing interface required by this type of engines. The hydrodynamic pressure sub-model will then be integrated in a complete OCR simulation code that could be used to predict trends for oil leakage, friction and wear. In parallel, an experimental setup will be built to validate the model and OCR performance by measuring oil consumption and oil film thickness in a representative controlled environment.