In the present work, the flow pattern in pipe flow has been simulated using low Reynolds number k-epsilon model. The CFD model has been extended to simulate the axial dispersion phenomena in both the transition and turbulent regions. An extensive comparison of the predicted axial dispersion coefficient with the experimental data has been presented along with the predictions of various models published in the literature. The proposed CFD model for axial mixing was found to give an excellent agreement with the experimental measurements. (C) 2003 Elsevier Science Ltd. All rights reserved.