Enhancement of the Lightning Protection System of Floating Roof Oil Tanks by Improving its Grounding System

Abstract

Lightning is a very complex natural phenomenon, which may result from a discharge between the cloud and the ground. It is one of the main hazards of fire in floating roof oil tanks. Many factors play an important role in the amount of damage to the tank due to a lightning strike. These factors include the amplitude of the lightning current, the type of lightning strike, and the configuration of the grounding system. This study was conducted to find out the effect of direct lightning on the floating roof oil tanks and to know the extent to which the efficiency of the tank grounding system is affected by high frequencies. where a numerical method based on the finite element method was presented to analyze the overvoltage distribution on large floating roof oil tanks. The simulation results showed that the amount of overvoltage generated on the floating roof was reduced by 20% and 47.4% for the first and subsequent lightning strikes, respectively. When the effect of the high frequencies is taken into account as a result of the soil resistivity reduction, especially in areas where the soil resistivity is more than 1000 Ω.m. In addition, a significant decrease in the value of excessive voltage is observed when using the new configuration of the oil tank grounding system.