SFB 1029: TurbIn - Substantial Efficiency Increase in Gas Turbines through Direct Use of Coupled Unsteady Combustion and Flow Dynamics

CRC 1029的目标是显著提高燃气轮机的效率，并应通过将燃烧概念向近似定容燃烧转变来实现。到目前为止，已经研究了两个概念。脉冲爆震燃烧是基于激波触发的极快燃烧，但也会引起较大的压力波动。通过无冲击爆炸燃烧的替代概念，这些在很大程度上减少，其中燃料的特定分层和声学现象的利用导致整个燃烧管的均匀自燃。CRC 1029的第三周期将另外包括旋转爆震燃烧。由于压力波以非常高的频率沿周向传播，因此该概念似乎也非常有希望在燃气轮机中实施。与常规燃气涡轮机过程相比，所有描述的燃烧概念都以周期性不稳定压力波为特征，因此将对燃气涡轮机内的涡轮机部件的操作条件产生显著影响。研究了有效降低压气机、燃烧室和涡轮机交界面压力脉动的方法和试验。此外，必须保证第一涡轮机级的充分冷却以及压缩机出口处的流动稳定性，因此，这是CRC 1029的进一步重点领域。一个目标是将额外的努力减少到最小，以保护整个燃气涡轮机的总体效率增益。在第三个阶段内，应在相关燃气涡轮机条件下，推动所制定的措施达到更高的成熟度。出于同样的原因，迄今为止完全基于成熟的热力学方法的发动机整体评估现在也将扩展到结构力学方面。在第三阶段，项目取得的成果将结合在演示平台的建立中。它应用于开发不同负荷状态下的过程控制策略，并为压缩机和涡轮机专用独立试验台的实验推导出代表性边界条件。

A significant increase of the efficiency of gas turbines is the objective of the CRC 1029 and shall be achieved by changing the combustion concept towards an approximately constant volume combustion. Two concepts have been investigated up to now. While the pulsed detonation combustion bases on an extremely fast combustion triggered by shock waves, it also causes large pressure fluctuations. These are largely reduced by the alternative concept of a shockless explosion combustion, where a specific layering of the fuel and the utilization of acoustic phenomena lead to a homogeneous auto-ignition of the whole combustion tube. The third period of CRC 1029 will additionally include the rotating detonation combustion. Due to pressure waves travelling in circumferential direction at very high frequencies, this concept seems to be very promising for implementation in gas turbines as well.In contrast to conventional gas turbine processes, all described combustion concepts feature periodically unsteady pressure waves and will thus have a significant impact on the operating conditions of the turbomachinery components within the gas turbine. Methods and experiments have been investigated to effectively reduce the pressure pulsation at the interfaces between compressor, combustion chamber and turbine. Furthermore, sufficient cooling of the first turbine stage as well as flow stability at the compressor exit must be safeguarded and have thus been further focus areas of CRC 1029. One objective was to reduce the additional effort to a minimum to protect the overall efficiency gain of the whole gas turbine. Within the third period, the developed measures shall be driven towards a higher degree of maturity within relevant gas turbine conditions. For the same reason, the holistic assessment of the engine, which was solely based on well-developed thermodynamic methods so far will now be expanded to look at structural mechanics’ aspects as well.Within the third period, the achieved results of the projects shall coalesce in the setup of a demonstrator platform. It shall serve to develop process control strategies in different load regimes as well as to derive representative boundary conditions for the experiments with dedicated stand-alone rigs of compressor and turbine.