Flow characteristic experiment on vector-enhanced dual-throat thrust-vectoring nozzle

Model tests of a vector-enhanced dual-throat thrust-vectoring nozzle were performed to obtain the internal flow characteristics,including the internal flow pattern and the static pressure distributions at different secondary flow pressure ratios.The test results indicate that after adding divergent part to the tail of traditional dual-throat vector-nozzle,the jet flow is deflected upwards beyond 20 degrees at a secondary flow ratio of 2.8%.Therefore the design concept of the vector-enhanced nozzle is feasible.In the concave cavity of the nozzle,the static pressure distribution of the vector-enhanced nozzle is basically the same as that of a traditional dual-throat nozzle.At the additional divergent part,the surface pressure of the bottom wall is obviously higher than that of the top wall,accounting for the vector angle augment.In addition,the vector angle increases monotonously with the pressure ratio of the secondary flow,but the vector enhancing effect of the divergent part remains basically unchanged.