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

随着地面交通的电气化进程缓慢但稳步推进，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，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没有实现。最好的解决方案仍然是提高发动机效率，以尽可能减少燃油消耗。大型燃气轮机已经达到了令人印象深刻的效率水平，但小型燃气轮机由于有限的燃烧温度以及高粘性和叶尖损失而仍然相对低效。为了实现大幅降低油耗，制造商被迫重新审视具有新视角的替代发动机配置。清洁推进的主要候选者之一是非往复式内燃机类型，其联合收割机了容积式发动机的高效率，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因其油耗而闻名，在用于航空航天应用之前需要减少油耗，以满足客户的看法，重量和即将到来的排放法规。通过面密封油控制环（OCR）的泄漏可能占机油消耗量的一半以上，并且是降低总机油消耗量的首要目标，因为它可以从当前值大幅降低，而不会对发动机耐用性产生重大影响。该项目旨在通过详细的建模和实验验证来改善发动机OCR。UdeS和P&WC团队将在以前的OCR模型的基础上，开发一种新的流体动压数值公式，该公式是为此类发动机所需的轨道面密封OCR-壳体接口量身定制的。然后，将流体动压子模型集成到一个完整的OCR模拟代码中，该代码可用于预测漏油、摩擦和磨损的趋势。与此同时，将建立一个实验装置，通过在代表性的受控环境中测量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.