Effect of eccentricity on jets delivered from a primary nozzle surrounded by secondary flow is studied experimentally. The eccentricity is achieved by offsetting the annular spacing of the co-flow passage, surrounding the center nozzle generating the primary jet. This is achieved by making a base plate with its center which is offset by 2 mm in the downward direction with the center of inner nozzle. The studies have been carried out in possible flow regimes of jet exiting from a convergent nozzle like subsonic and correctly and underexpanded sonic conditions. The experiments were carried out for primary nozzle exit Mach numbers of 0.3, 0.5, 0.8 and 1.0 at correct expansion. The studies in underexpanded regime were conducted for nozzle pressure ratios (NPR) of 3 and 4. The eccentricity in the co-flow jet leads to 38% reduction in the supersonic core length at NPR 3 and 60% at NPR 4 in comparison with concentric co-flow configuration. The eccentricity also leads to early mixing of co-flowing jet.

实验研究了偏心对从被二次流包围的主喷嘴输送的射流的影响。偏心是通过抵消共流通道的环形间距来实现的，围绕中心喷嘴产生主射流。这是通过制作一个底板来实现的，底板的中心与内喷嘴的中心向下偏移 2 毫米。这些研究是在从收敛喷嘴喷出的可能流态中进行的，如亚音速和正确和未膨胀的声速条件。实验是针对 0.3、0.5、0.8 和 1.0 的主喷嘴出口马赫数在正确膨胀下进行的。针对 3 和 4 的喷嘴压力比 (NPR) 进行了膨胀不足状态的研究。与同心协流配置相比，协流射流的偏心率导致 NPR 3 处的超音速核心长度减少 38%，NPR 4 处的超音速核心长度减少 60%。偏心也导致共流射流的早期混合。