Measurements of engine gas temperature, velocities and early flame propagation

该子项目主要集中在缸内测量的时间和空间的波动，有关气体性质和火焰传播，在点火的关键过程。为了确定壁热通量和自燃的动力学，由于激光诱导的痕量荧光，将在光学可访问的发动机内绘制温度波动的高分辨率图像。湍流输运过程的附加信息将通过二维粒子图像测速（PIV）在相同的位置获得。因此，利用这些数据，可以评估近壁气体性质的LES结果，并进一步研究循环变化对自燃后早期火焰传播的影响。这是通过一种特殊的纹影技术进行的，其图像序列的kHz速率适合于光学引擎的弯曲几何形状。这些结果被用于鉴定子项目的化学发光测量。

The sub-project mainly focuses on in-cylinder measurements of fluctuations in time and space, regarding gaseous properties and flame propagation, during the crucial process of ignition. To determine the wall heat flux and the kinetic of auto-ignition, high-resolution images of temperature fluctuations will be mapped within an optical accessible engine, due to laser-induced trace-fluorescence. Additional information of turbulent transport processes will be obtained at the same locations by two-dimensional Particle Image Velocimetry (PIV). Hence with this data, the performed LES results of near wall gaseous properties can be assessed.Further the influence of cyclic variations on the early flame propagation after auto-ignition will be investigated. This is carried out by a special Schlieren-technique with kHz rates of image sequences adapted to the curved geometry of the optical engine. These results are used to qualify the chemiluminescence measurements of sub-project .