Experimental investigation on the operating modes of an integrated tug-barge system

Now-a-days, Integrated Tug-barge system (ITBS) is very much popular for transportation purposes in inland waters. In the ITBS, the barges are connected to the tug rigidly. The ITBS does not allow the barges to pitch or heave independently relative to the tug. The ITBS can be operated in different modes viz., tandem towing, side towing and pushing modes. For the design of propulsion system for ITBS, the resistance of ITBS is the primary input. This resistance can be predicted either analytically or numerically. But, experimental method is a proven one to estimate the resistance accurately so that the experimental results can be directly used for the final design of ITBS. Hence, in the present study, an experimental investigation has been carried out on a typical ITBS for different modes of operation to get insight knowledge on the resistance characteristics of ITBS. A 1:25 scale model was tested in an 82m × 3.2m × 2.5m towing tank at Ocean Engineering Department, IITM, Chennai for the three modes of operation. The resistance test results are analyzed and presented with discussions in this paper. © 2006: The Royal Institution of Naval Architects.