Mobile Harbor, Alabama navigation study : ship simulation report

Mobile Bay is a large estuary located in the southwest corner of Alabama, which connects to the Gulf of Mexico. Mobile Harbor contains the only port in the state that supports ocean-going vessels. Some of the larger vessels calling on the port experience transit delays and limited cargo capacity, so a study was conducted by the US Army Corps of Engineers, Mobile District (CESAM), and the Alabama State Port Authority to investigate channel improvements. In 2017, the US Army Engineer Research and Development Center (ERDC) assisted CESAM in screening proposed deepening and widening alternatives in Mobile Bay by completing a Feasibility Level Ship Simulation (FLSS) study using the ERDC Ship/Tow Simulator. These lower-resolution databases from the FLSS study were used as a foundation to complete a more robust navigation study in 2020 to test the proposed modifications to Mobile Harbor. During this study, three main areas were focused on: a bend easing, a passing lane, and a turning basin. Testing of the proposed design was evaluated over the course of 2 weeks with eight pilots. Assessment of the proposed modifications was accomplished through analysis of ship simulations completed by experienced local pilots, discussions, track plots, run sheets, and final pilot surveys.

Simulation Models for Offshore Port Service Concepts

Offshore port service concepts were developed to flexibly respond to the emergence of large container ships and the increase in port trade volume. As one such offshore service concept, a mobile harbor system has recently been proposed. Although it is possible to effectively increase the capacity of existing ports through these mobile harbor systems, the methodology for evaluating the performance of a traditional port is limited when applied to evaluating the performance of the mobile harbor system. In this study, we develop a simulation model to analyze the mobile harbor system. The simulation model reflects the operating characteristics of the mobile harbor, and the performance metric of the system can be derived from the model. The results can be applied to capacity planning of a port system with a method that reduces search space. We applied our method to the Surabaya port in Indonesia to derive the optimal mobile harbor design that satisfies the required service level.