Simulation of Ship Motions

The NYK Group has set “safe ship operations” as one of the priority goals in the “initiatives creating new value that will transform the NYK Group,” which is aimed through ESG management. Ensuring the safety of crews and ships and preventing cargo damages are our important missions. One of the major causes of accidents is large ship motions. Since the characteristics of excessive ship motions that may lead to accidents that vary greatly and depend on the type of ship and its cargo, it is important to select an appropriate simulation method for each ship type. MTI has studied on appropriate simulation methods for each situation,　and simulated the potential ship motions in the actual seas. The results of the simulations enable us to screen for hazardous conditions that lead to large ship motions and provide navigation support information for crews. We are studying appropriate simulation methods and simulating ship motions for more ship types, thereby contributing to safe ship operations and better transportation quality.

Ship motions are greatly affected by the ship’s speed, course, and encountered waves. Among those factors, ship’s speed and course can be adjusted by maneuvering, while waves the ship encounters are the factor not to be adjusted by maneuvering. For this reason, wave forecasts are utilized for a voyage planning to avoid sailing in stormy seas. However, there are still risks that ship encounter extreme large wave because forecasts have an uncertainty and sometimes underestimate the wave height. In such cases, crews need to figure out the actual wave condition somehow and maneuver to avoid large ship motion. Since wave observation platforms are very limited in open sea, waves are visually observed by crews in normal operation. At MTI, we are working on the installation of wave RADAR that analyze wave information from navigational RADAR signals. Wave RADAR is the one of the sources to provide wave information that is independent to wave forecasts and visual observations. We are also trying to evaluate the accuracy of wave RADAR data and utilize it to predict ship motions in the actual seas. Our current aim of research is utilization of wave information on shore. We are continuing our research to contribute to safe ship operations.