Research of combinative altitude difference between advanced knife and scraper

Firstly, based on the Ottosen-four parameter failure criterion, establish material constitutive mode with damage factor. Then, in circumstance of large non-linear dynamic finite element software (ANSYS/LS-DYNA), build the combinative cutting model of advanced knife and scraper under different altitude difference. In addition, three-dimensional dynamic simulation of cutting characteristics is applied to study the discipline between the amount of cut rock, cutting force and cutting efficiency. From the simulation result, it can be concluded that the cutting efficiency of scraper increases before the altitude of advanced knife and scraper comes to 33mm (optimal one), after which it will gradually reduce until to the final stabilized state. However, within a range of 30mm altitude difference, the cutting force on scraper goes down along the altitude difference´s growing in number, which guarantees that advanced knife can protect scraper and create favorable working conditions. Meanwhile, the amount of rock cut by scraper fluctuates relatively slightly, improving the cutting efficiency of scraper. For scraper in rotary cutting process, the cutting force on outside is almost 17% greater than that on inside.