Plasma sprayed thermal barrier coatings (TBCs), applied in internal combustion engines, can have a profound impact on the apparent rate of heat release. Upon fuel jet contact with the piston wall, the heat loss seems to increase compared to an uncoated piston and combustion appears delayed. Permeable porosity of plasma sprayed TBCs is identified as one of the possible causes for this unwanted effect. In this article the impact of open porosity and sealing of the TBC surface are investigated with single cylinder engine experiments and with simulations. Based on the results, a mechanism is presented to explain the observations.

中文翻译：

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热障涂层孔隙率对轻型柴油机燃烧和热损失的影响

应用于内燃机的等离子喷涂热障涂层（TBC）可以对表观热释放速率产生深远的影响。当燃料喷射与活塞壁接触时，与未涂层的活塞相比，热损失似乎增加，并且燃烧出现延迟。等离子喷涂 TBC 的渗透性孔隙率被认为是造成这种不良影响的可能原因之一。在本文中，通过单缸发动机实验和模拟研究了开孔率和 TBC 表面密封的影响。根据结果​​，提出了一种机制来解释观察结果。