QUICK METHOD FOR DETERMINATION OF THE VELOCITY PROFILE OF THE AXIAL SYMMETRICAL SUPERSONIC LIQUID JET

摘要

To be able to apply the theoretical model of abrasive jet for calculations essential in real-time control, it is necessary to find out very quick and precise method for description of the liquid stream structure. The simplified model was derived to determine the liquid jet attenuation in the medium outside the nozzle. The relationships for description of the equivalent jet structure evolution provided the presumption of the jet axial symmetry were derived. Taking into account, the well-known principles of hydrodynamics and some unorthodox views of the liquid jet formation inside the nozzle, the set of equations for the calculation of the cross-sectional velocity field inside jet was derived. The set of equations is useful for determination of both the attenuation and the jet structure development in the medium surrounding the nozzle. The derivation of analytical relationships is completed by experimental results obtained in the Institute of Geonics. The experimental data were measured using a special sensor developed for the jet structure investigation. The theory was also compared with summarised results of foreign authors dealing with the jet structure problems both theoretically and experimentally. All presented results (both theoretical and experimental) were obtained in air, but the theoretical relationships are appropriately valid in other media, e.g. in liquids.