The development of a port, or just a new terminal in a port, is a big undertaking. There are financial, environmental, political, regulatory and practical aspects to be considered and carefully weighed. These projects normally take a great deal of effort and time in the design and approval phases, with the actual construction being a culmination of a long, expensive preparation phase. Preparation is the key to the success of the project, and the best preparation will employ the use of simulation. A simulation study of a port development project is best accomplished when approached as a three-step process.
Before starting the process, it is critical to define desired study objectives. With those objectives defined, many of the other elements in the process fall into place naturally. We often find that the process of defining objectives becomes iterative and that modifications are identified in each step. The key here is to recognise that time spent in defining objectives/modifying objectives will result in a better more focused study.
The first step in the process is to accurately identify the area to be examined. A very effective method of doing this is to produce a visual simulation model of the area. In the case of terminals or ports this can include the approach channels out to the sea buoy; thus a digital model with visual graphic overlay is produced that portrays the key geographic features of the area, as well as aids to navigation and significant landmarks. Photographs of the port or terminal facility are used or, in their absence, engineering drawings of the proposed facility are compiled to produce a representation of the project. In addition, the hydrography of the area is reproduced in the form of accurate current and channel conformation models. Weather considerations are also factored in, and the simulation model is capable of replicating the variety of weather conditions experienced in the area. It is important to identify the ships and tugs, which are being considered for the project. They, too, need to be modelled with visual, digital and hydrodynamic fidelity. The identification of all these elements will flow naturally from a welldefined set of objectives. The product of this, the Modelling step, then is a representation of the project that is accurate in visual, digital and hydrodynamic details and can therefore be used to evaluate the overall goals of the project.
The second step is the actual Evaluation of the objectives of the project. Once the objectives are identified, then scenarios can be developed to actually test the various elements. Examples of elements to examine might be: Limits of current or wind that allow safe navigation in the waterway, the adequacy of the approach channel, the size requirement of the turning basin, the adequacy of existing aids to navigation and the identification of additions required, the berth configuration and its angle/ position, and the identification of tug requirements. While some of these elements are more important than others, they all need to be considered; the size and shape of the turning basin, for example, may have significant impact on project cost and environmental impact.
With objectives defined and scenarios developed, the testing begins using interactive simulation. Different combinations of environment and ships/tugs are placed in the simulation, and an experienced mariner familiar with the area actually manoeuvres the ship. Criteria to determine acceptable/unacceptable results are defined and, based on the results, recommendations are made and a detailed report produced. This report can be used as the basis for re-engineering if required, as a starting point for further evaluation, for presentation to the Coast Guard if additional navigation aids are required, and as part of a submission to regulatory agencies in the licensing and permitting process. Depending on the requirements, specialised studies to examine risk can also be conducted. An example is an allision analysis. In this type of study, interactive simulation is used to determine the likelihood of an allision, if a transiting vessel has a casualty or equipment failure. Further a determination can be made as to the preventive measures required; i.e., stand by tugs in the terminal area, if the risk of allision is deemed high. Another example of this type of evaluation is a passing ship analysis. Interactive simulation is used to determine the magnitude of the forces placed on the mooring lines of a ship tied to a wharf when another ship passes. The full range of bow wave and suction effects can be accurately measured and a determination made as to the risk involved to the moored ship. This analysis can lead to risk mitigation recommendations such as speed limits and/ or a change in the location of the channel axis.
The third step of the process is Training. Once the project has been modelled and a final design produced on the basis of the evaluation conducted, then movement to the final step is possible. This is a crucial part of the process since humans will be controlling the ships and the tugs in the waterway. The training programme is a joint effort between the customer and the simulation facility. Once training objectives are identified, a programme combining classroom and interactive simulation is developed. The training programme emphasises procedures to minimise risk and maximise safety. Communications procedures including standard commands are practiced and committed to routine. Tug combinations and different methods of employment are experimented with in order to determine best practices. Emergency procedures are rehearsed and proficiency is developed in coping with difficult and unexpected situations. Laws and regulations are discussed and compliance practiced. An important aspect of the training will be interactive simulation so each of the participating players can actually perform, as they will in real life. Thus the tug master will actually control his unit as directed by the pilot, who will be in a separate simulator with the ship master and selected ship personnel. The three will form the pilotage team and be able to practice their interaction in the simulated environment so when actually in the waterway the entire system operates properly. The training programme is required prior to the commencement of operations to ensure all pertinent issues have been addressed and at periodic intervals to ensure currency and to train new hires.