Computational Study of an Axisymmetric Dual Throat Fluidic Thrust Vectoring Nozzle for a Supersonic Aircraft Application
Computational Study of an Axisymmetric Dual Throat Fluidic Thrust Vectoring Nozzle for a Supersonic Aircraft Application
复制标题
DOI：
10.2514/6.2007-5084
复制
发表时间：
2007-07
期刊：
影响因子：
--
通讯作者：
K. Deere;J. Flamm;B. Berrier;Stuart K. Johnson
中科院分区：
文献类型：
--
作者：
K. Deere;J. Flamm;B. Berrier;Stuart K. Johnson
本文研究了轴对称型变膨胀比双喉喷管概念，以确定其对推力矢量和喷管性能的影响。采用非定常reynolds -average Navier-Stokes计算流体力学代码PAB3D指导超音速飞机喷管的设计。轴对称双喉喷嘴概念在美国宇航局兰利研究中心的喷气出口测试设施中进行了静态测试。喷管几何设计变量包括喷射周向跨度、空腔长度、空腔收敛角和喷管扩张比，分别对应于起飞和降落、中爬升和巡航等工况。当喷嘴压力比达到10，二次喷射速率达到一次流量的10%时，确定了喷嘴内部性能和推力矢量性能。在相同的注射面积和孔数下，60度注射跨度总体上优于90度注射跨度，与计算结果一致。当喷射速率小于7%时，60度喷射范围内的推力矢量角比90度喷射范围内的推力矢量角高1.5 ~ 2度。减小空腔长度可以提高推力比和流量系数，但会降低推力矢量角和推力矢量效率。在测试的喷射速率范围内，将空腔收敛角从20度增加到30度，推力矢量角增加了1度，但对系统推力比和排放系数产生了不利影响。双喉口喷管的膨胀比为1.0（在两个相等的最小面积之间有一个空腔），产生了最佳的推力矢量性能。在整个飞行包线中，变膨胀比几何结构并没有提供典型超声速飞机期望的流量系数和系统推力比的改善。在中程爬升和巡航条件下，可变几何设计影响了推力矢量角的实现，但可以实现一些推力矢量控制，这可能会影响飞机的配平。在NPR测试的范围内，与可变几何形状的双喉喷嘴相比，固定面积、膨胀比为1.0的双喉喷嘴在推力矢量和喷嘴内部性能方面提供了最佳的整体折衷。
An axisymmetric version of the Dual Throat Nozzle concept with a variable expansion ratio has been studied to determine the impacts on thrust vectoring and nozzle performance. The nozzle design, applicable to a supersonic aircraft, was guided using the unsteady Reynolds-averaged Navier-Stokes computational fluid dynamics code, PAB3D. The axisymmetric Dual Throat Nozzle concept was tested statically in the Jet Exit Test Facility at the NASA Langley Research Center. The nozzle geometric design variables included circumferential span of injection, cavity length, cavity convergence angle, and nozzle expansion ratio for conditions corresponding to take-off and landing, mid climb and cruise. Internal nozzle performance and thrust vectoring performance was determined for nozzle pressure ratios up to 10 with secondary injection rates up to 10 percent of the primary flow rate. The 60 degree span of injection generally performed better than the 90 degree span of injection using an equivalent injection area and number of holes, in agreement with computational results. For injection rates less than 7 percent, thrust vector angle for the 60 degree span of injection was 1.5 to 2 degrees higher than the 90 degree span of injection. Decreasing cavity length improved thrust ratio and discharge coefficient, but decreased thrust vector angle and thrust vectoring efficiency. Increasing cavity convergence angle from 20 to 30 degrees increased thrust vector angle by 1 degree over the range of injection rates tested, but adversely affected system thrust ratio and discharge coefficient. The dual throat nozzle concept generated the best thrust vectoring performance with an expansion ratio of 1.0 (a cavity in between two equal minimum areas). The variable expansion ratio geometry did not provide the expected improvements in discharge coefficient and system thrust ratio throughout the flight envelope of typical a supersonic aircraft. At mid-climb and cruise conditions, the variable geometry design compromised thrust vector angle achieved, but some thrust vector control would be available, potentially for aircraft trim. The fixed area, expansion ratio of 1.0, Dual Throat Nozzle provided the best overall compromise for thrust vectoring and nozzle internal performance over the range of NPR tested compared to the variable geometry Dual Throat Nozzle.