hrvatski

Primarna realizacija temperaturne ljestvice od trojne točke argona do trojne točke vode

The independent primary realization of the temperature scale (ITS-90) in the Laboratory for Process Measurement (LPM), as the national temperature standard, is achieved in the range from the triple point of mercury (-38.8344 °C) to the freezing point of copper (1084.62 °C). To be able to participate in the scientific metrological projects and comparisons in the field of low temperature measurement, LPM is developing a new measurement system for the realization of the triple point of argon (-189.3442 °C). This includes design and characterization of the system along with the definition of the of the associated experimental method and measurement uncertainty assessment of the realization. For the realization of the triple point of argon, sealed fixed point cell for accommodating long-stem platinum resistance thermometers, was selected, as this type of thermometers represent the backbone of traceability dissemination at LPM. Fixed point cell is going to be immersed in cryostat filled with liquid nitrogen and conditions for the realization of the triple point of argon will be achieved through the automatic regulation of the outflow of nitrogen vapours from the cryostat. Performance of the measurement system will be verified through the bilateral comparison with the equivalent temperature standard. Development of this system will ensure traceability of temperature measurement in the range from triple point of argon to the triple point of water (0.01 °C), along with the improvement of low temperature measurement capabilities. Furthermore, involvement in the process of thermodynamic temperature approximation will be enabled, with the respect to the recent redefinition of kelvin as well.

temperatura, primarna realizacija, ITS-90, trojna točka argona

nije evidentirano