The characteristics of each ship type were analyzed according to the results of the above tests and design of the new ships proceeded on that basis. Models of the new ships were also built and tested.
* Overall evaluation (FY 1995)
Overall evaluation was conducted for each sip design, based on the results of the model tests, and the final ship design proposal was determined on the basis of this evaluation. The details and results of this process were as follows.
1.1 Basic Design
In the first phase of research, the basic design was conducted for each of the hypothetical ship types in this research project. To select the ship types and their particulars, the survey work was carried out on the ship's cargo volume and allowance for ship draft due to shallow water depth, features of ports in the NSR and the NSR in general. The results of these examinations formed the basis for the research that followed on the design of a multipurpose cargo ship that could navigate from the port of Murmansk through the NSR to Japan (with the assumption of some inland river navigation). The principal particulars of the ship are summarized in Table B-1. The engine room of the ship was located in the stern. The ship has a double-sided and double-bottomed structure with the ballast tanks at the sides, fore and aft. The main engine output was determined by estimating power based on a prediction formula of ice resistance, to satisfy the stipulated icebreaking capability. A controllable-pitch propeller was designed to be driven directly by a diesel engine. Both conventional and nozzle propeller types were also examined. Following determination of the ship type and its main particulars, design work commenced. Recognizing that the shipbuilding industry of Japan has little experience of constructing icebreaking cargo ships, a systematic study of the ship types and their performance was executed using tank tests and theoretical calculations. To do this, ship designs combining the three bow types and two stern types shown below were examined.
Table B-1 Principal particulars of icebreaking cargo ship for coastal NSR navigation
