Vessel Utilisation – Part 4: An overview of bespoke post processing

Introduction

So far in this series we have prepared and run a number of simulations and considered the results in Mermaid, all with the aim of answering the question:

“When should we take the trenching vessel on hire, relative to the installation vessel?”

We saw in the last post that our base case offset (32 days) is a fairly good position, however, we think there might be opportunity to improve on this.  The issue we have is that our post-processing requirement is outside the type of charts and tables offered by Mermaid.  This bespoke requirement is not a limit to us being able to answer the question we have – in this post we’ll look at how we can post process outside Mermaid.

Mermaid simulation files

When a simulation is performed Mermaid generates two zip files:

Generated zips

Each of these files contains a number of csv files and all are fully human readable:

csvs in zip

There are full descriptions of the contents of these files available to our user community on the Mermaid User Support Portal.  In these files we can find a number of different data points, including timestep by timestep descriptions of the tasks and vessels usage (for example, the log below), and details on task start and end points:

Vessel log

Post Processing

Since we know the format of these files we can extract data from them, either through the use of scripts, or manually.  In this analysis we use a script to determine when the vessels went on and off hire relative to the cable lay vessel going on hire (i.e. all our results will be days before/after the on hire of the cable lay vessel).  Running this script for the results of our different scenarios generates a number of charts which we can use to advance our understanding of the operation.

Code and console

Post Processing Outputs

Next steps

In the next post in this series we’ll look at the results we generated using our post processing script and consider what they mean for our on hire schedule.