Method for validating an invasive temperature measurement system

A validating device, comprising:

• an input interface configured to:
• receive at least a first temperature data of an invasive temperature measurement system of a medium;
• and
• receive a second temperature data of a non-invasive temperature measurement system;
• and
• a data processing device, the data processing device configured to:
• provide a first temperature data of the invasive temperature measurement system of a medium, the medium surrounded by a vessel wall enclosing the medium;
• provide a second temperature data of a non-invasive temperature measurement system, the non-invasive temperature measurement system thermally contacting an outside surface of the vessel wall enclosing the medium to measure the surface temperature of the surface of the vessel wall;
• determine a temperature of the medium based on the second temperature data, medium properties and properties of the vessel wall;
• wherein the determination of the temperature of the medium is model based, and wherein the model includes a heat transfer characteristics of a boundary layer of the medium;
• and
• compare the first temperature data with the determined temperature of the medium to validate the invasive temperature measurement system.