System and Method for Non-Invasive Determining of a Fluid Temperature

A system for non-invasive determining of a fluid temperature of a fluid in a pipe, comprising a surface temperature sensor disposed at a pipe surface of the pipe; a reference temperature sensor disposed outside of the pipe; a data interface, configured for receiving nominal process parameters; a process parameter sensor, configured for determining at least one measured process parameter, wherein the at least one measured process parameter relates to measured parameters of a process that relates to the fluid in the pipe; and a process model, configured for determining a calculated fluid temperature of the fluid in the pipe by using the determined surface temperature, the determined reference temperature, the received nominal process parameters and the at least one measured process parameter.