Validation of a fiber optic based dynamic thermometer

Traceable, reliable measurement of combustion temperature is important because it can improve the understanding of the combustion process and provide a mechanism for the optimisation of engine power, fuel consumption, and emissions. These measurements are performed under highly dynamic conditions, with temperature changes of up to ∼3300 K occurring on a millisecond timescale. Conventional temperature sensors based on contact thermometry (e. g., thermocouples) are inadequate in this context, due to their slow response time (∼10 ms), temperature limitation (≤ 2100 K), drift, and perturbation of the combustion process. To address this challenge, with particular reference to internal combustion and diesel engines, NPL have developed a novel ultra-high-speed combustion pyrometer within the framework of the European joint research project DynPT - Development of measurement and calibration techniques for dynamic pressures and temperatures, part of the European Metrology Programme for Innovation and Research (EMPIR).