Probabilistic modelling of offshore fires

Probabilistic models are proposed to represent the heat radiated from offshore pool and jet fires. The basic variables that influence the shape of the flame of a pool and a jet fire are described as well as the heat transfer mechanisms from the flame. A first-order second moment approach is proposed to describe the uncertainty of the estimates of the radiated heat as a function of the uncertainty in the input variables as well as the sensitivity of the results to the different variables. Since the pool and jet fire models are not represented by an analytical expression which could be handled easily, the sensitivity factors are estimated based on the numerical calculation of the partial derivatives of the variables used in the fire model. An example of the radiation in a tubular member is provided, identifying the critical variables from the uncertainty point of view.