Transient liquid crystal thermography using a time varying surface heat flux
نویسندگان
چکیده
Heat transfer measurements are required in a wide range of fields, for example to validate new cooling concepts turbomachinery, assess the performances heat exchangers, and provide data numerical simulations. Thereby transient methods often applied local resolution. A particular challenge is posed by complex flows, where determination coefficients with commonly heater mesh method can prove difficult, instance cases which flow take different paths leading mixing flows at temperatures, difficult reference temperature. One way address these systems foil method, experiment driven constant flux generated surface under study, instead temperature variation flow. However, accuracy measurement remains an open issue compared method. Here we show modification uses linearly increasing improve accuracy, especially low regions. The validated measuring single circular jet perpendicularly impinging on flat plate, comparing results correlation available literature. Results good agreement literature, while providing considerable improvement respect flux. presented here, reaches similar uncertainty values as state art versions regions, better high Additionally, it allows easier implementation certain problems, provided that optical access guaranteed curvature addition foil.
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ژورنال
عنوان ژورنال: International Journal of Heat and Mass Transfer
سال: 2021
ISSN: ['1879-2189', '0017-9310']
DOI: https://doi.org/10.1016/j.ijheatmasstransfer.2021.121718