Openclsim: Discrete Event Dredging Fleet Simulation to Optimise Project Costs
WODCON XXIII - Dredging is changing - The Practice. The Science. The Business.
G.J. de Boer, J.P. van Halem, B. Hoonhout, F. Baart, M. van Koningsveld
"Van Oord successfully implemented discrete event simulation to operate more cost-efficiently and environmentally friendly. Discrete event simulation allows for optimization of a mixed fleet (hoppers, cutters, barges,...) in the tender as well as in the execution stage. Optimizations can target a range of performance indicators, like cost, fuel, spill and potentially also CO2 emissions. Together with TU Delft, Van Oord co-developed the open-source Python package OPENCLSIM as a tool for its discrete event simulations. OPENCLSIM facilitates the mimicking of day-to-day dredging operations with minimal mathematical abstractions and can therefore be operated, modified, and extended with common engineering skills, making it independent of third parties and suitable for a community-based approach. The community approach to OPENCLSIM focuses on facilitating a wide community of users to create modular extensions. Van Oord contributed by implementing a layered structure to the OpenCLSim package that allows for sharing modules on a conceptual level within the wider community, while keeping project and company knowledge proprietary. The divide between open-source and proprietary is determined entirely by the user, for each module separately, and may change over time: initially proprietary modules can still (partially) be opened later on. Van Oord's latest contribution to OPENCLSIM is a so-called 'container reservation'. This concept allows multiple pieces of equipment, with different capabilities, to jointly execute the activities of a dredging cycle. This concept was one of the extra components needed by Van Oord to successfully apply OPENCLSIM in an ongoing large dredging project, the dredging and reclamation works for the Fehmarnbelt tunnel. Here multiple barges are serviced by 1 cutter. This paper describes the technical and practical implementation of OPENCLSIM in Van Oord's work processes based on two examples: internal tender tool, and execution support. We foresee a future growth in OPENCLSIM as our sector needs to engage in increasingly complex optimizations, continuously balancing, project duration and costs vs sustainability aspects like energy consumption and emissions. "
Keywords: simulation, optimization, workability, environmental impact, sediment management