Development of a CFD Primary Cooling Fan Model for Prediction of Air Flow in the Primary Cooling Zone of Line 2 at United Taconite

Abstract

A CFD model of the Line 2 Primary Cooling Fan (3A) has been developed and demonstrated to be capable of reproducing the fan curve as supplied with the fan. The effect of air temperature and inlet damper position have been simulated and used to produce a series of flow-pressure curves for the unit as it operates in the plant. The plant fan model appears capable of reproducing the air survey velocity pressure profiles measured on July 11, 2006. The United Taconite CFD Cooler Model was then used to develop a family of system resistance curves based on cooler operating parameters. The fan and system resistance curves, when combined, allow the fan operating point to be defined, from which flow can be predicted. Several linear models were developed and then used to predict plant performance, using the July 11, 2006, operating point. The predictions fall within 8% on a volume flow basis, within 6% on a mass basis. Additional operating points are needed to demonstrate the model's predictive capability over a flow range. Based on the results in this report, it appears possible that an on-line flow prediction model could be developed with additional research.