New and Improved formulations of Pressure Sensitive Paints for Aerodynamics

压敏涂料(PSP)是一种空气动力学研究技术，它允许测量整个空气动力学表面的压力，从而允许表面上的载荷积分。除此之外，该技术还允许在传统传感器无法定位的区域进行压力测量。当正确地应用于表面时，可以进行非稳定压力测量，从而可以研究抖振、空腔振荡，甚至是瞬时气动流动等现象。这一增加的能力代表着工程师研究空气动力流动和车辆的能力发生了一步变化。PSP方法依靠氧的发光猝灭来使一种称为发光体的光活性分子失活。目前正在使用的发光体自本世纪初以来一直保持不变。将发光体应用于表面的最常见方法涉及使用透氧性粘结剂材料。这种粘合剂材料又一次保持了近20年的不变。目前唯一可从商业供应商获得的PSP配方是基于高度氟化的分子(铂五氟四苯基卟啉、铂(TFPP)和氟化结合剂(聚合物)，因此价格极其昂贵，氧猝灭性能仍然不理想。本项目将研究传统PSP配方(铂(TFPP))的替代方案，目的是开发比目前商业上可用的配方更敏感、更有效和更便宜的新PSP配方。这将通过合成一系列的卟啉发光体来实现，这些发光体要么含有显著降低的氟化程度，要么根本不含氟化基团，而且不含重金属铂。这些新分子的三重态氧猝灭特性将通过发光光谱和单重态氧量子产率来确定。然后，最有希望的候选材料将被用一系列具有高透氧性的常见聚合物进行粘结剂测试，然后在模拟风洞条件下评估涂层配方和PSP性能的最佳组合。

Pressure-Sensitive Paint (PSP) is an aerodynamic investigation technique that allows for the measurement of pressure over an entire aerodynamic surface allowing for integration of loads over surfaces. In addition to this, the technique allows for pressure measurement in areas where traditional sensors cannot be located. When applied correctly to a surface, unsteady pressure measurements can be made allowing for investigations of phenomena such as buffet, cavity oscillations, and even transient aerodynamic flow. This added capability has represented a step change in the ability of engineers to investigate aerodynamic flows and vehicles. The PSP method relies on the luminescence quenching of oxygen to deactivate a photoactive molecule known as a luminophore. Luminophores currently under use have remained unchanged since the early 00s. The most common methodology of applying the luminophore to a surface involves the use of an oxygen permeable binder material. This binder material again has remained unchanged for almost 20 years. The only PSP formulation currently available from commercial suppliers are based on heavily fluorinated molecules (platinium pentafluoro-tetraphenyl porphyrin, Pt(TFPP) and fluorinated binding agents (polymers), are therefore extremely expensive and the oxygen quenching properties remain unoptimised.This project will investigate alternatives to the traditional PSP formulation (Pt(TFPP)) with the aim of developing new PSP formulations that are more sensitive, efficient and cheaper than current commercially available formulations. This will be achieved by synthesising a range of porphyrin luminophores that contain either a significantly reduced degree of fluorination, no fluorinated groups at all and that do not contain the heavy metal platinum. The triplet oxygen quenching properties of these new molecules will be determined by luminescence spectroscopy and the singlet oxygen quantum yields determined. The most promising candidates will then be taken forward for binder testing with a range of common polymers that possess a high oxygen permeability, and then the best performing combinations assessed for coating formulations and PSP performances in model wind tunnel conditions.