联焰板宽度对单凹腔驻涡燃烧室流线形态的影响

Effects of radial strut width on flow structure of single-cavity trapped vortex combustor

为了研究联焰板宽度对单凹腔驻涡燃烧室流线形态的影响,设计了一个带扩压器和内外机匣的单凹腔驻涡燃烧室,并在此基础上进行了常温、常压状态下的冷态流场试验,试验中设置联焰板宽度分别为40、30、20 mm。研究结果表明:在主流中心截面(PM)上,凹腔内存在双涡流动结构,主涡位于凹腔的中间位置,副涡位于主涡与主流之间;在联焰板中心截面(PA)上,不同的联焰板宽度会形成两种不同的流线形态,当联焰板宽度较宽时,凹腔内为单涡流动结构,仅存在主涡结构,主涡回流气流沿联焰板向火焰筒下壁面流动;当联焰板宽度较窄时,凹腔内为双涡流动结构,主流气流卷入联焰板后方。

In order to study the flow structure of different width of radial strut,a single-cavity trapped vortex combustor with diffuser and casings was designed.Unburnt flow field experiments were carried out by changing the width of radial strut on the combustor.Experiments were accomplished at atmospheric pressure and temperature.The main parameters of the experiments were shown as follows:the width of radial strut was 40,30,20 mm while the number of radial strut was constant.The results showed that on the central section of mainstream(PM),there were two vortices in the cavity.The main vortex was located in the middle of cavity,and the secondary vortex was located between the main vortex and mainstream.On the central section of radial strut(PA),different width of radial strut would form two different flow structures.When the width of radial strut was wider,the cavity had a single-vortex flow structure,which meant that only the main vortex existed in cavity.The reflux airflow from main vortex flowed along the radial strut to the lower wall of the liner.When the width of radial strut was narrower,the cavity had a double-vortex flow structure,which meant that the meanstream flowed to the behind of radial strut.