The objective of the Star-shape comparison is to establish the degree of equivalence among the reference laboratories in Europe on thermal conductivity measurements of high temperature insulation using steady-state techniques by star-shape comparison from 150 °C up to 650 °C.
Funded by the EMRP SIB52 project Metrology for thermal protection materials. PTB are responsible for independently collecting the data, not participating in the measurements.
Final Report 2017-03-30
In a Star-Shape (SS) comparison procedure, the thermal conductivity of one insulation reference material with a thicknesses of 48 mm was measured at mean specimen temperatures from 150 °C to 650 °C by reference laboratories in Europe. The instruments involved are the National Standard instruments, the Guarded Hot-Plate (GHP) apparatuses at NPL, LNE and CMI; the commerical GHP at LNE; the industrial GHP at FIW; and the High Temperature Thermal Conductivity Measurement Apparatus (HTTCMA) at BFKH. The objective of the comparison between the results of the different partners and their individual instruments is to show if the requirements of the new EU regulations for equivalence not worse than 5 % can be achieved.
The measurements started in February 2016 and were completed in all the reference laboratories involved in July 2016. NPL piloted the comparison. PTB, as independent party not participating in the star-shape comparison measurements, is responsible for collecting the measurement results of all participants and the analysis and report of the data. The objective of agreement within 5 % has partially been achieved.