Flow calibration system and method for determining temperature uncertainty

The invention relates to the technical field of flow measurement, in particular to a flow calibration system and a temperature uncertainty determination method, the flow calibration system comprises a flow calibration device, a control module and a plurality of temperature detection units, the flow calibration device comprises a to-be-detected fixed pipeline and a standard fixed pipeline, and a plurality of standard Venturi nozzles are arranged in the standard fixed pipeline; the temperature detection unit passes through the standard fixed pipeline, and the control module is configured to determine the temperature uncertainty of the standard fixed pipeline based on the position of the standard fixed pipeline and the temperature detection depth of the temperature detection unit. The detection data of the temperature detection unit capable of measuring the most accurate temperature data is reasonably selected for analysis, the deviation between the detection temperature data and the actual environment temperatu