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This paper details a methodology for quantification of errors and uncertainties of a finite element heat transfer model applied to a Ruggedized Instrumentation Package (RIP). The proposed verification process includes solution verification, which examines the errors associated with the code's solution techniques. The model was subjected to mesh resolution and numerical parameters sensitivity studies to determine reasonable parameter values and to understand how they change the overall model response and performance criteria. To facilitate quantification of the uncertainty associated with the mesh, automatic meshing and mesh refining/coarsening algorithms were created and implemented on the complex geometry of the RIP. Similarly, highly automated software to vary model inputs was also developed for the purpose of assessing the solution's sensitivity to numerical parameters. The model was subjected to mesh resolution and numerical parameters sensitivity studies. This process not only tests the robustness and numerical error with computation time. Agglomeration of these studies provides a bound for the uncertainty due to numerical error for the model. An emphasis is placed on the automation of solution verification to allow a rigorous look at uncertainty to be performed even within a tight design and development schedule.

Spotting occurs in wildland fires when fire-lofted embers or hot particles are carried by the wind and fall in areas of unburnt yet flammable vegetation leading to ignition of new, discrete fires. Significant work has been conducted on predicting the trajectories of the embers but little fundamental work is available related to the capability of these embers or particles to ignite vegetation. This paper consists of an experimental and theoretical study of ignition of fuel beds by hot metal particles. Both laboratory and real life fuel beds have been tested. Spherical steel particles with diameters in the range 0.8 to 19.1 mm heated to temperatures between 500 and 1300oC are used in the experiments. A relationship between the size of the particle and temperature required for flaming or smoldering ignition is found in powdered cellulose. These results are used to assess a model based on Hot Spot Ignition Theory to determine the particle sizetemperature relationship required for ignition of a cellulose fuel bed. The model qualitatively predicts the ignition response of the fuel to a given particle size and temperature. Similar experiments were also conducted using pine needles as the fuel bed.