Heat transfer through impingement cooling of a rotating cylinder

通过旋转圆筒的冲击冷却进行热传递

• 批准号: 437324525
• 负责人: Professor Dr.-Ing. Hans-Jörg Bauer
• 金额: --
• 依托单位: Institut für Thermische Strömungsmaschinen (ITS)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/437324525?language=en
• 关键词: Heat; transfer; through; impingement; cooling

The geared turbofan engine is a current concept for reducing the specific fuel consumption and noise emissions of civil aircraft engines. By using a high-performance transmission, larger bypass ratios can be achieved, resulting in increased propulsion efficiency. In order to ensure safe operation of the planetary reduction gearbox, precise knowledge of the thermal budget is required. The heat release in the lubricating film due to the sliding of the tooth flanks in mesh can be determined sufficiently precisely by the elastohydrodynamics. A model for the heat transfer during impingement cooling of the gears, however, is not yet available. The proposed project should contribute to a better understanding of the impingement cooling process and to the modelling of the impingement cooling process of spur gears. Experimental investigations of the heat transfer in impingement cooling have shown that the highly unsteady heat transfer process in gear cooling is dominated by the impact process. This sub-process shall be investigated fundamentally by experimental investigations through impingement cooling of a rotating cylinder. The experimental data will be used to characterise the flow behaviour during jet impact. Furthermore, a correlation for the heat transfer is to be derived. In a second part of the project, the findings from the experiments on the rotating cylinder will be compared with the existing experimental data on impingement cooling on the spur gear. It shall be investigated whether and how the model for cylinder cooling can be transferred to the impingment cooling of spur gears. The detected differences will be used to define experiments for a second application period.

齿轮传动涡扇发动机是目前民用飞机发动机降低油耗和噪声排放的一种新概念。通过使用高性能变速器，可以实现更大的涵道比，从而提高推进效率。为了确保行星减速箱的安全运行，需要精确的热预算知识。用弹性流体动力学方法可以足够精确地确定啮合齿翼滑动引起的润滑膜热释放。然而，齿轮碰撞冷却过程中的传热模型尚未得到。所提出的项目应有助于更好地理解冲击冷却过程和对直齿轮冲击冷却过程的建模。碰撞冷却换热实验研究表明，齿轮冷却的非定常换热过程主要由碰撞过程控制。这一子过程需要通过旋转气缸的撞击冷却实验研究来进行根本的研究。实验数据将用于描述射流撞击时的流动特性。此外，还将推导出传热的相关关系。在项目的第二部分，旋转圆柱的实验结果将与现有的正齿轮碰撞冷却实验数据进行比较。研究了圆柱冷却模型是否可以推广到正齿轮的冲击冷却，以及如何推广到正齿轮的冲击冷却。检测到的差异将用于定义第二个应用周期的实验。