Simplified Model to Represent the Installation Process of Subsea Equipments

During the installation of a subsea module it is extremely important to guarantee that the structure will not be damaged, as this would imply in elevated costs and hazards to the environment. In order to minimize these risks, the installation process can be simulated inside software that use numerical modeling by considering different environmental conditions, so that a safer procedure with more adequate operational window can be achieved. However, these software can be very expensive, and this kind of simulations usually takes a long time, making it very convenient when one has access to a simplified model, capable of simulating different conditions in a short period of time, while still providing reliable results. This paper presents a simplified model developed in Python programming language, which uses a fourth-order RungeKutta method to solve the equation of motions that governs a vertical installation process. The installation ship’s motions were applied to the top of the cable, simulating its connection to a crane aboard, and then the motions of the suspended equipment and the cable tension could be calculated. The results obtained through the use of this simplified model were then compared to the ones obtained through the use of a much more complex model using the OrcaFlex® software and to experimental data.