Experimental and numerical investigation of shallow water effects on resistance and propulsion of coupled pusher-barge convoys

Model tests for three representative configurations of modern inland coupled pusher-barge convoys were performed to experimentally and numerically assess calm water resistance and propulsion characteristics in deep and shallow waters. The configurations consisted of a pusher boat coupled with one, two, and four barges. Obtained was insight into calm water resistance of such systems and benchmark data to validate numerical methods. Although the barges being pushed were identical, their arrangement had a significant effect on the efficiency of the convoys. Power required to transport a unit payload was lowest for the third configuration. Numerical resistance tests were carried out using a Reynolds-Averaged Navier–Stokes solver for the first configuration in deep and shallow waters, with varying water depth to draft ratios of H/T=∞,2.0,1.5 and 1.2. The computations were validated against model test measurements.