Mathematical modelling of ideal flat jets impact

The problem of finding the parameters of stationary jets, outgoing from the place of impact of two incoming flat ideal jets with free boundaries and possessing the identical speed, but various width, has no solution, because there are four unknown parameters (the width and the angular position of two outgoing jets) in three independent equations, following from mass conservation law and an impulse. Various models are widely used nowadays for obtaining the missing equation, but they lead to contradictory results. In this research we propose a new model, which made it possible to develop algebraic dependences to determine the parameters of an outgoing jet. According to the model, the width of these jets is defined by the average width of the incoming jets and the corner between them and doesn’t depend on difference in the width of these jets. We checked the reliability of the model offered, as well as the models known today, by comparing the results of calculating the width and the angular position of the outgoing jets with the numerical calculations executed in ANSYS AUTODYN in Euler system of coordinates. The numerical calculations showed reversibility of a jet current: if we change the direction of a current of the outgoing jets to the incoming ones, we obtain values of the width and the angular position of the original incoming jets. Thus, we established that the results in calculating the width of the jets will be coordinated with the results of the numerical calculations in the wide range of parameters of the incoming jets. We concluded that the developed dependences which determine the angular position of the outgoing jets describe the numerical calculations in the range between the incoming jets from 90 to 110 degrees better than the other models. To increase accuracy in calculating the angular position of the internal outgoing jet, we developed the dependence based on approximating the results of the numerical calculations. The research is of great interest to experts, who work on behavior of technological errors in cumulative streams. The received results can be useful to specialists in jet equipment and in explosive bonding.

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