An online device and method for predicting at least one fluid flow parameter in a process (which comprises a bounded flow domain having disposed therein a pre-determined matrix) includes a computer and/or process steps whereby: (i) a memory receives a database, the database comprising location information for a plurality of nodes or particle pathways in the matrix; (ii) input data is received from the process, and (iii) the at least one fluid flow parameter is calculated from the database and the input data. Preferably, structure and/or process steps are provided to adjust the database in the event that the input data does not correspond with at least one pre-determined flow state.