Abstract:

The five-stage cylindrical stepped-wall observation chamber and cylindrical observation chamber are designed to explore the control method of interior ballistic stability of bulk-loaded liquid propellent gun(BLPG). The propagating process of twin gas jets in liquid medium is experimentally studied. The experimental data indicates that the stepped-wall structures can restrain the positive feedback mechanism of the Taylor cavity and Kelvin-Helmholtz instability. Based on the experiment, a three-dimensional mathematical model is established. The expansion process of twin gas jet in liquid medium in different observation chambers is simulated. The distribution maps of density, pressure and temperature were obtained. The simulated results show that, in the cylindrical stepped-wall observation chamber, the effect of turbulent mixing of gas-liquid along the radial direction is enhanced and the axial turbulent intensity is suppressed due to the induction of steps, and the outlines of twin jets are smooth relatively. The simulated results of axial displacements of twin gas jets in liquid coincide well with the experiment data.

Key words: ordnance science and technology, twin gas jet, turbulent mixing, expansion shape, numerical simulation