Softsensor for the characterisation of the process fluid

This paper introduces an intelligent fan equipped with a softsensor for the volume flow rate and composition of a two-component process fluid, as e.g. often found in chemical processes. This is done by combining the fans characteristic data with those of cheap pressure and temperature sensors as well as the mixture laws of a two-component gas. An example estimating the percentage of butane for a combustion flow is given. As the experiments show, the estimation uncertainty of the softsensor is 2 % for the butane concentration and 3 % for the volume flow rate and thus of the magnitude of the uncertainties of the used input data.