Applied Mathematics Seminar

Over the last three years losses of about $400,000,000 of cargo and container ships have occurred due to fire and explosion and in all cases part of the cargo was calcium hypochlorite (solid pool chlorine). The events originated in the regions of the holds where this material was stored and due to its known highly reactive and self heating properties it became the prime suspect as the cause, much to the consternation of the manufacturers.

The mathematics of self-ignition of bodies of simple geometry is a well understood area of nonlinear mathematics and when the basic physicochemical parameters of the material are known reliable predictions of the ignition conditions can be made. However in this case the physicochemical parameters have turned out to be badly characterised in a very dangerous way leading to predictions which were highly optimistic. In addition, and equally importantly, the effect of interaction of numerous self -heating bodies occupying the same closed container and thus producing a cooperative effect had not been recognised and modelled until the present work.

The material is shipped with as many as 400 40kg kegs per container but the UN testing protocol only requires testing of the ignition temperature of a single keg on its own. Modelling of this interaction effect is playing a crucial role in investigations covering Tahiti, South and Central America, Europe, USA, China, Japan and Australia. Publishable results will be reported, both theoretical and experimental.