Reduction of fluid resistance using the rheological characteristics of a polymer-surfactant solvent is research that contains many aspects, such as the theory of the drag reduction process, historical journey, and ongoing current research development. Many studies have been conducted, but it is challenging to know all existing and new research threads. The present investigation was conducted using literature studies regarding drag reducing agents. This research will also discuss the characteristics of flowing fluids and their effects on the velocity profile with friction factor of flowing fluids in smooth circular straight pipe geometries based on experimental, theoretical approaches. It concludes with aspects of research conducted around reducing drag using drag reducing agents, ideas about innovations, structuring overlook in testing, and modification of the fluid flow state.

Sea transportation such as that by container ships has an essential role in the economy both locally and internationally. Ships are a major commodity in distributing goods over long distances due to their relatively low price compared to air shipping. The study implemented an optimization method using heuristic algorithms with ship route selection to minimize operational costs based on the parameters of mileage between 12 ports in the Asia-Pacific region. The ship speed, engine power, and fuel prices at each port are processed using asymmetric traveling salesman problem modeling (ATSP). The research uses three different algorithms to compare with the performance of the traveling salesman problem, namely the nearest neighbor algorithm, simulated annealing, and a genetic algorithm, with an objective function of keeping fuel costs that ships will incur to a minimum. The results show that the genetic algorithm provides the route with the lowest fuel cost.

Design optimization on the Indonesia N219 seaplane catamaran is necessary to provide better service to rural islands of Indonesia. This research aims at decreasing drag using a design based on biomimicry by imitating the hydrodynamic characteristics of sailfish (Istiophorus platypterus) for pontoon floats. The design is then validated using a numerical fluid test using ANSYS Fluent to see the reduction in drag due to the change from a conventional or Wipeline^® 13000 design to a biomimetics adaptation design. Next, further optimization was carried out based on the adaptation design based on trim tests, clearance tests, and deadrise angle dimensions suitable for biomimicry designs at Froude number speeds of 0.4 to 0.7. The design results with the adaptation of biomimicry show that a change in the design with this optimization affects a drag reduction that reaches 30% of the total drag generated by the conventional design.

Pipe routing in ship design presents significant challenges because of its time-consuming nature and the need for considerable attention to detail. In recent years, the decreasing number of pipe designers has impacted the quality of pipe-routing designs. However, optimizing pipe routing is crucial for reducing construction costs and ship production time. This study focused on optimizing the procedure and routes, considering over 500 pipes throughout the engine room of an 82,000-ton Panamax bulk carrier with three decks. Procedure optimization was based on a genetic algorithm and a system that considered individual pipe characteristics, such as type, diameter, and length. For pipe-route optimization, we used the Dijkstra algorithm, which aims to provide the shortest pipe routing by minimizing branching, bending, crossing, and obstacle avoidance. Pipe-routing optimization was divided into “basic” and “detailed” designs to derive rough and detailed routes, respectively. The basic design allowed intersections and horizontal bending, while the detailed design provided a route without intersections and minimized all bending. The optimized design was compared with pipe routing designed by diameter and shorter-path orders. In ship construction, pipe-routing optimization reduced the overall cost of pipe routing by 7% compared to other systems that typically use diameter and shortest-route orders. The study’s findings highlight the practical cost benefits and potential applications of the pipe-routing process in ship construction.

Nergy efficiency is a global goal in the fight against global warming. Research on reducing drag is one of the ways to improve energy efficiency. The research method used is the injection of micro-sized bubbles and ultra-fine bubbles used in the barge ship model. Microbubble Drag Reduction (MBDR) and Ultrafine Bubble Drag Reduction (UFBDR) are two methods that can play an essential role in reducing drag on the surface of the ship's hull. Factors that can affect the effectiveness of these methods are the injection ratio, location, and coefficient of drag produced by both methods. The injection method discussed the use of the method, which was reviewed on a 2-meter towing tank and compared the two injection methods. The results provided by this research are to determine the injection ratio and the optimum injection location on the model ship and compare the effect of reducing drag and drag coefficient. The increases total resistance reduction of 6.87% compared to the reduction in resistance by microbubble injection.

Container ports are pressured for efficiency while reducing greenhouse gas (GHG) emissions under decarbonization rules. Simulation-based operational planning frameworks are increasingly being explored for container terminal decarbonization and coordination analysis. This study fills the gap by developing a trace-driven offline digital twin (DT) framework integrated with a discrete event simulation model decision support for tactical planning and emissions assessment at Tanjung Priok International Container Port. Historical terminal operating system data were used to reproduce real operational conditions and evaluate alternative operational strategies without disrupting live terminal operations. Using deterministic simulations, the effects of coordination strategies, such as yard allocation, equipment deployment, and truck–vessel synchronization, on crane productivity, turnaround time, equipment utilization, and emissions were analyzed. The strategies impacted productivity, truck turnaround time, equipment utilization, and lifecycle GHG emissions. Monte Carlo simulations, the uncertainty and variability of environmental outcomes under different operational conditions were analyzed. The results show that coordination-based strategies outperform simple expansion in reducing congestion and emissions. Truck–vessel synchronization strategies and workload redistribution across yard space and time provide substantial operational and environmental benefits. The proposed framework should therefore be interpreted as a trace-driven offline DT discrete event simulation environment for tactical scenario evaluation rather than a fully synchronized real-time digital twin.