In this work, the motion, deformation, break-up, and deposition of molten copper droplets transported by high speed, high pressure, and high temperature gas flow along a steel internal flow path are examined numerically using a volume of fluid based approach. The study of the related phenomena is motivated by the erosion and fouling patterns along flow paths caused by such droplets. Good correlation to literature was achieved for a single drop impact. Methods were applied to multiple drops moving with gas flow in a main flow channel with a by-pass with the strength of the flow varied by changing the initial pressure in the main channel gas by up to a factor of four. The amount of copper removed from the main flow path grows from 58% to 87% when the driving pressure is quadrupled. A greater portion of the copper in the by-pass section is solidified as well with 90% solidified for the higher pressure, compared to 60% at the lower pressure. Solidification of the copper and melting of the steel require the proper combination of the molten copper location, the temperatures in the copper, steel, and gas, and the velocity of the transporting gas flow. The knowledge gained from the study can be applied to mitigate the fouling and erosion that may develop along internal surfaces. Because of the need for a small element size to prevent copper mass loss, the use of this method with complex three dimensional geometries may be limited. Published by Elsevier Ltd.