Numerical Prediction of the Cooling of Burnt Cable for the Prevention of Re-Ignition Available to Purchase

Fires in the cable structures are a serious danger for the offshore facilities. Inflammations of the cables are mostly caused by cable overheating as a result of power loads in the net or by the shortcut circuits. Fire extinguishing comes, in the first place, to neutralization of the external flame on its surface. However, even when the external flame is prevented, the re-ignition of the cable’s insulation may happen in case its metal core has not been sufficiently cooled down to a safe temperature level. It is therefore important to clarify the dynamics of the core cooling under the influence of the flow of extinguishing agents in order to manage the temporal characteristics of the entire process. The current paper reports a numerical model of a hot cable cooling under the influence of external flow. The model resolves the temperature fields as in the cable as in the surrounding media in connection with the flow profiles of the cooling agent. Several cooling scenarios are considered for the problem: natural convection of the cooling gas around the cable, and forced heat utilization due to an induced gas-water flow directed towards the cable. The model is validated with the use of experimental data presenting a suitable agreement with empirics.