The paper considers the problems that arise when creating a filter for purifying liquids from solid impurities with a self-cleaning function. To realize the self-cleaning effect, the filter element is placed in an ultrasonic cavitation medium, which is formed by introducing ultrasonic vibrations with an intensity exceeding the threshold of cavitation under these conditions into the liquid in the region of the filter baffle. Due to the secondary effects accompanying the phenomenon of ultrasonic cavitation, namely shock waves, cumulative jets and microflows, the constant cleaning of the filter baffle pores is ensured. But, at the same time, there is a problem of ensuring the durability of technological filtering equipment due to cavitation erosion of the structural materials from which the filter element and housing parts are made. Numerical modeling of the impact interaction of a contamination with the surface of a filter element was carried out, and an expression of the law of energy conservation was presented that takes into account the dominant factors affecting the interaction process. The components of the energy source acting on the contamination during contact with the fixed filter surface are substantiated and considered.