Removal of the iron oxide layer from a fuel tank wall: Effect of nozzle distance and impact angle on water jet pressure

• A simulation model of a high-pressure water jet cleaning fuel tank was established. • Effects of nozzle distance and impact angle between the nozzle and fuel tank wall were investigated. • A theoretical model was determined to predict impact pressure as a function of nozzle distance and impact angle. • These two variables were independent and had both linear functions on impact pressure. The development of hydraulic technology has led to the increasing application of high-pressure water jets in industrial fields such as metal surface cleaning, cutting, etc., because of its environmental friendliness. This study used multiphase fluid dynamics simulation to investigate the impact pressure of water jets acting on the fuel tank surface with changes in the nozzle distance and impact angle of the nozzle to the tank wall. A predicting model of the impact pressure based on these two investigated variables was also built as a basis for the calculation and design of hydraulic systems for tank cleaning. The results show that when the nozzle distance and impact angle increase, a higher pressure is required at the nozzle inlet to clean the fuel tank wall. The effects of these two factors on the water jet impact pressure are independent of each other, and both have linear functions. The findings in this work can be applied to all types of industrial tanks with different sizes and shapes, such as circles, ellipses, rectangles, trapezoids, etc., as well as various tank materials, such as iron, steel, aluminum alloy, bronze, etc.