EXTERNAL PUBLICATIONS

SUMMARY

Assessment of the hazards posed by the storage of flammable or toxic liquids in large tanks can be assisted by the use of mathematical models to calculate the consequences of leakages. These consequences may include fires or explosions from dispersion of flammable vapours, or harm to persons from inhalation of toxic vapours. One component of such models is a mathematical representation of the spreading of a liquid pool, and in recent years a number of pool spread models have been proposed and implemented. However, there are a number of issues in the formulation of the spreading models that have yet to be resolved. In particular, one area of uncertainty is the boundary condition applied at the front of the spreading pool. Boundary conditions which are generally accepted as applicable to the spread of oil on water and to the dispersion of a cloud of dense gas in air may not be applicable to the spread of a liquid on land, as the balance of competing physical phenomena at the spread front is quite different. Resolution of the uncertainties this creates has been hampered by a lack of reliable experimental data at a large scale. As a result, the Health and Safety Executive have contracted Advantica to carry out a series of 'liquid spread on land' experiments at their Spadeadam Test Site to provide a sufficiently detailed database to help to resolve this issue. This report describes the resulting programme of 58 experiments, studying the flow of liquid across a bund floor and measuring the amount of liquid that escaped the bund for a wide range of bund geometries.

This report and the work it describes were funded by the Health and Safety Executive (HSE). Its contents, including any opinions and/or conclusions expressed, are those of the author(s) alone and do not necessarily reflect HSE policy