Modeling of heat flow from burning oil tanks

A model was developed to determine the density of heat flux by radiation from a fire in a vertical steel tank with an oil product. The model takes into account the deformation of the flame under the in fluence of wind: the tilt of the flame axis and the expansion of its base to leeward. The proposed ap proach is based on the known empirical dependencies of the flame length and the angle of its deviation from the vertical axis depending on wind speed, specific mass burn rate of the liquid, and tank diameter. These dependencies are used to determine the flame length at an arbitrary point on the flame base. This makes it possible to construct the equation of the radiating surface of the flame in a parametric form. The resulting surface has a conical shape with an elliptical base extended beyond the tank from the lee ward side. The relative expansion of the flame base outside the tank increases with the wind speed and decreases with the diameter of the tank. An algorithm for calculating the heat flux density by radiation from a flame to an arbitrary site given by spatial coordinates and a normal vector has been developed. The algorithm uses the coverage of the flame base with a regular grid, followed by the application of numerical differentiation methods to determine the normal vector to the radiating surface of the flame and numerical integration methods to estimate the view factor between the flame and the site heated by the fire. It is shown that the expansion of the tank base leads to a significant increase in the heat flux density on the leeward side of the tank. The results obtained can be used to determine the consequences of the thermal impact of the fire on neighboring oil tanks and other process equipment, as well as to determine the safe location zones for equipment and personnel involved in localizing and eliminating the fire.