二元收-扩喷管气动喉道控制数值模拟

Numerical simulation of two-dimensional convergent-divergent nozzle with pneumatic throat control

设计了收敛段为圆转方段的二元收-扩喷管,对喉道面积气动射流控制方案进行了数值模拟,分析了喷管出口宽高比、落压比、射流角度对喉道面积和喷管性能的影响.结果表明:喷管喉道矩形截面宽边壁面附近的静压小于窄边壁面附近的静压,并且随着出口宽高比的增大,宽边壁面附近的静压逐渐减小,窄边壁面附近的静压逐渐增大;在同样的落压比下,出口宽高比增大,喉道面积控制范围(RTAC)、喉道面积控制效率(ETAC)增大,总压恢复系数减小;出口宽高比一定时,随落压比的增大,RTAC,ETAC先减小而后基本保持不变,总压恢复系数增大;ETAC随射流角度的增大而增大.

The two-dimensional convergent-divergent nozzle with a circle-to-square con- vergent part was designed. The project of the throat area control with pneumatic injection was numerical simulated. The influences of nozzle exit width-to-height ratio, pressure drop ratio and injection angle on the throat area and nozzle performance were analyzed. The results show that the static pressure near the wide side in the rectangular nozzle throat sec- tion is lower than that near the narrow side. The static pressure near the wide side decreases and that near the narrow side increases with the increase of exit width-to-height ratio. At the same pressure drop ratio, the range of throat area control （RTAC） and the efficiency of throat area control （ETAC） increase while the nozzle coefficient of total pressure recovery decreases with the increase of exit width-to-height ratio. At a fixed exit width-to-height ratio, RTAC and ETAC decrease firstly and then keep at the same level while the nozzle coeffi- cient of total pressure recovery increases with the increase of pressure drop ratio. ETAC increases with the increase of injection angle.