The British Royal Navy is currently deploying a new CO2 removal system for use in disabled submarines when the air circulation and monitoring system is shutdown. This uses LiOH based technology in the form of Reactive Polymer Curtains (RPCs) to absorb CO2 from the air.
Frazer-Nash Consultancy Ltd. has developed a Computational Fluid Dynamic (CFD) capability to numerically simulate the airflow and CO2 absorption reaction in a realistic survival situation in the forward compartment of a Trafalgar Class submarine.
The CFD modelling approach incorporates a reaction model for the RPCs. The reaction model is designed to depend only on the surrounding CO2 concentration and the quantity of active material remaining in the RPCs, and so can be applied to any simulation involving RPCs.
The RPC reaction model has been validated against experimental data from RPC performance trials in a hyperbaric chamber. The CO2 monitors throughout a simulated version of the chamber (using CFD) were found to be closely aligned with the experimental results throughout the trial, therefore validating the RPC reaction model.
This validated capability has now been used to simulate realistic survival situations on Royal Navy Submarines to assess the effectiveness of RPCs at lowering CO2 levels in a survival situation and help with the guidelines for RPC deployment and positioning.