Modelling of thermal effects in a slim tin fixed-point cell

International journal of metrology and quality engineering

article

Sergio A. Carvajal¹  J. Herney Ramírez²  Andrés J. Bohórquez¹  Ciro A. Sánchez¹ 

[1] Temperature and Humidity Laboratory, Instituto Nacional de Metrología de Colombia − INM;Departamento de Ingeniería Química y Ambiental, Universidad Nacional de Colombia

关键词: Slim fixed-point;    modeling;    thermal effects;    ITS-90;   

DOI  :  10.1051/ijmqe/2019017

学科分类：土木及结构工程学

来源: EDP Sciences

【 摘 要 】

Slim fixed-point cells are an economic and suitable alternative for calibration of industrial platinum resistance thermometers, which are widely used in research and industrial applications. The most relevant disadvantage of slim cells is related with thermal effects produced by interactions between the cell and the furnace used for the realization of the fixed-points. This work presents the implementation of a two-dimensional numerical model that considers the transient heat transfer due to conduction, radiation and latent heat. The main goal was to evaluate different geometrical parameters in the design of slim fixed-point cells. Results show that thermal effects are mitigated when the annular distance between interior and exterior walls of the crucible is maximum, while the length of the cell and the thermo-well must be setup according to the temperature gradients in the furnace to avoid undesirable heat fluxes.

【 授权许可】

CC BY