| Popis: |
The paper discusses the gas-dynamical disturbances in the nozzle jet-flow, dis-covered by numerical simulations, caused by mechanical-shaped jet obstacles, immersed in the exit area of the nozzle flow for thrust vector control purposes. External profiled tab shaped as a dome deflector is used to disturb the flow in the exit area, which provides the comprehensive 3-D nozzle separated flow zones with different high gradients of flow stream parameters. Discovered complexity of the flow pattern in the 3-D nozzle separated zone is exploited by complex CFD simulations and used for the numerical calculations, implemented by FLUENT commercial code. Pressure and temperature distributions data along the nozzle walls, as well as on the deflector wall, are used to estimate induced lateral and thrust forces by pressure integral. Induced forces estimated by numerical simulations and hot gases nozzle tests are compared as relative efficiency values to prove the quality of numerical simulations. Numerical calculations are carried out in the nozzle, obstacle, and the gap flows showed good agreement to the calculated and measured induced forces. The main aim of the developed method is to establish an approved calculation tool to compare and choose thrust vector control possibilities based on tabs with different forms of immersion in the external jets. |
