Uncertainty measurement of two color two dye laser-induced fluorescence thermometry and application thereof to superheated liquid jet

Abstract

Flash boiling spray is a highly interesting phenomenon in various industries, and it is known that bubble generation and growth by phase change and heat transfer in a metastable state governs the development of the spray. To understand this phenomenon deeply, knowing the temperature field is crucial. Therefore, 2c LIF, one of the most promising non-intrusive measurement techniques, should be thoroughly checked for its strengths and weakness. In this experimental study, the performance of thermometry using fluorescein disodium and sulforhodamine was evaluated by using a jet of water at various injection temperatures from 25 – 84.5 °C. The precision was assessed according to the error propagation model considering shot and camera noise and compared with the measured one. The measured precision was around 2 % over 60 °C with available room for further improvement. As potential error sources, the effects of stray light inside the chamber and morphology dependence resonance are discussed. The jet of which injection temperature is about 91 °C was injected into the chamber in a pressure of 5 – 11 kPa, and two disintegration regimes were observed according to superheat, the number of generated nuclei, and resultant heat transfer. The temperature fields of superheated liquid in both regimes were measured, and their physical plausibility is discussed.