基于多孔压敏荧光粒子的空间压力场与速度场同步测量技术研究

The aim of the proposed research is to combine pressure-sensitive paint with particle image velocimetry and develop a simultaneous flow pressure and velocity measurement technique based on porous pressure-sensitive fluorescent particles. The pressure-sensitive particles in this technique consist of pressure-sensitive luminescent material PtTFPP and hollow silica particles with porous surface, which are excited by a pulsed laser after being seeded into the flow, and the simultaneous measurements of pressure and velocity fields can be achieved with a double-camera system through precise timing control. The pressure field will be obtained using the lifetime method in PSP technique, and the velocity field will be acquired by applying PIV cross-correlation. The proposed research will significantly enhance the signal level of the fluorescent particles by adopting porous hollow particles and high-performance fluorescent materials, and will also improve the measurement accuracy by using ICCD camera and developing advanced image-processing algorithms. This new flow measurement technique is able to directly measure spatial pressure field, and the simultaneous measurements of pressure- and velocity-field provide advanced and accurate experimental support for the intensive studies on complicated flow problems such as turbulence and fluid-structure interaction, and for the validation of computational models as well.

本项目旨在融合压敏涂层（PSP）测量技术和粒子图像速度场（PIV）测量技术，从而发展一种基于多孔压敏荧光粒子的空间压力场与速度场同步测量技术。压敏粒子由压敏荧光材料PtTFPP与表面多孔的空心SiO2粒子结合而成，将粒子播撒到流场中后，使用脉冲激光进行激发，通过对双相机测量系统进行精确的时序控制，可实现空间压力场与速度场的同步测量。其中，空间压力信息通过测量压敏粒子荧光寿命获取，而速度信息通过对压敏粒子图像进行PIV互相关处理获取。荧光粒子所采用的多孔空心结构和高性能荧光材料可使荧光信号强度显著增加，结合使用ICCD相机和发展先进图像处理算法则可提高测量精度。这一新颖的实验流体测量技术能够通过直接测量的方式获取空间压力场，而空间压力场与速度场的同步测量技术则可为湍流、流固耦合等复杂流动问题的深入研究以及数值计算模型的验证提供一种先进并且精细的实验技术支撑。

本项目基于多孔压敏荧光粒子开发了一种新型的流场压力测量技术。项目执行过程中，按照研究计划先后完成了压敏荧光粒子的制备及优化，压敏荧光粒子标定系统的设计建造，空间压力场-速度场同步测量系统的构建，图像处理算法的研发以及实验验证等各项研究工作。掌握了压敏粒子与快响应压敏涂层的制备技术，使其压力测量精度达到现有PSP技术的水平，响应时间达到100微秒以内；同时开发了寿命法测量系统，在标定设备中进行了空间压力场与速度场的同步测量，通过了原理性验证，较好地完成了既定的研究目标。基于项目的研究成果，已在Experiments in Fluids, Measurement Science and Technology以及AIAA Journal等实验流体力学顶级期刊发表SCI论文10篇，申请专利共3项。本项目开发的快响应压敏涂层与寿命法测量技术，初步解决了旋转叶片表面压力测量的瓶颈问题，已先后应用于涡轮增压器性能测试与直升机旋翼气动测试。该技术在民用与国防相关的气动测试领域有着良好的应用前景。此外，项目进行过程中广泛开展了国内交流与国际合作，对相关领域的发展起到了促进作用。