Tracer-free, non-intrusive, time- and space-resolved temperature and scalar measurements

航空运输的增长，以及未来电力中心对基础和平衡热力的需求，产生了对低排放、高效率燃气轮机的迫切需求，特别是在NO、CO和烟尘方面。决定这些污染物在产品气体中产生的关键变量是本地瞬时产品气体温度和本地燃料分数。气体温度的巨大波动以及污染物产生对温度的指数依赖性意味着，如果没有适当准确的局部温度测量的瞬时统计数据，就不可能预测燃烧中的NO、CO和碳烟。然而，在实际设备中很少有这样的测量来验证模型。高压辐射装置中的局部瞬时温度测量需要光学技术，这对于工业实验室来说是相当复杂的。这项提议旨在推广一种简单得多的技术，目的是允许对温度、压力和水蒸气进行无示踪剂的局部测量。激光诱导光栅光谱学(LLS)已被证明即使在高辐射、易产生烟尘的环境中也能工作，并且还可以使用易于获得的1064 nm的激光波长对额外的目标标量(水蒸气、压力)进行局部测量。该技术使用电致伸缩模式和该波长范围内的弱吸收光谱线，从而能够测量实际设备中的温度和相对水浓度。该技术的信噪比随着压力的增加而提高，这对现实设备来说是一个显著的优势，特别是在燃气轮机等容易产生大量辐射光度的环境中。该项目将把该技术目前的能力从点测量扩展到空间分辨的线测量。最后，它将把泵浦激光波长扩展到近红外，这将释放该技术的能力，使其能够使用高重复频率的工业激光，对一系列广泛存在的物种(水、二氧化碳和碳氢化合物)使用强吸收线。该项目的最终成果将是开发一种在高温、高压和实际反应流中进行非侵入性温度和物种测量的仪器和方法，只需要相当精度的以前技术的一小部分成本。演示测量将在高压、高温、逼真的工业设施中进行。在这些测量过程中产生的数据还将使研究人员和开发人员能够审查和验证工业中强大的反应流动模型，并为清洁能源转换设备的优化开辟了可能性。技术转让计划是通过与一家公司(Dantec)合作确保的，该公司已经将类似的仪器打包并商业化。一旦仪器开发和演示成功完成，计划将验证测量扩展到劳斯莱斯的其他工业设施。最后，该项目还将为与加的夫能源CDT相关的博士生提供机会。

The growth in air transport, and the need for base and balance thermal power in an electricity-powered future centres creates a pressing need for low emission, high efficiency gas turbines, particularly regarding NO, CO and soot. The key variables determining the production of these pollutants in the product gases are the local instantaneous product gas temperature and the local fuel fraction. The large fluctuations in gas temperature, and the exponential dependence of pollutant production on temperature means that predictions of NO, CO and soot in combustion are not possible without suitable accurate statistics of instantaneous local temperature measurements. Yet there are very few such measurements in practical devices to validate models. Local instantaneous temperature measurements in high pressure radiant devices require optical techniques which are rather complex for industrial laboratories. This proposal aims to extend a much simpler technique for the purpose to allow tracer free local measurements of temperature, pressure and water vapour. Laser-induced grating spectroscopy (LIGS) has been shown to work even in highly radiant, soot-prone environments, and may also enable local measurements of additional target scalars (water vapour, pressure) using the easily accessible Nd:YAG laser wavelength of 1064 nm. The technique uses both the electrostrictive mode and weak absorption spectral lines in this wavelength range to enable measurements of both temperature and relative water concentrations in realistic devices. The signal to noise of the technique improves with pressure, a significant advantage for realistic devices, especially in environments such as gas turbines, which are prone to large amounts of radiant luminosity. The project will extend the current capabilities of the technique from point measurements to spatially resolved line measurements. Finally, it will extend the pump laser wavelength into near infrared, which will unlock the ability of the technique to use strong absorption lines for a range of widely available species (water, carbon dioxide and hydrocarbons), using industrial lasers at high repetition rates. The final outcome of the project will be the development of an instrument and method for non-intrusive temperature and species measurements in high temperature, high pressure practical reacting flows, requiring only a fraction of the cost of previous techniques of comparable precision. Demonstration measurements will be produced in a high pressure, high temperature, realistic industrial facility. Data produced during these measurements will also allow researchers and developers to review and validate robust reacting flow models for industry and open up the possibilities for optimisation of clean energy conversion devices. The plan for technology transfer is ensured by partnering with a company (Dantec) that has already packaged and commercialised similar instruments. An extension of the validation measurements to other industrial facilities at Rolls-Royce is planned once the instrument development and demonstration has been successfully concluded. Finally, the project will also offer opportunities to PhD students associated with the Energy CDT at Cardiff.