采用直接模拟方法,研究气泡在浮力作用下的变形机理及气泡尾部驻涡形成机理。用二阶时空精度的变密度投影方法解Navier-Stokes方程,用VOF(volume of fluid)方法捕捉界面。获得了气泡平衡时的上升速度,并探讨气泡内部环流和气泡尾部驻涡...采用直接模拟方法,研究气泡在浮力作用下的变形机理及气泡尾部驻涡形成机理。用二阶时空精度的变密度投影方法解Navier-Stokes方程,用VOF(volume of fluid)方法捕捉界面。获得了气泡平衡时的上升速度,并探讨气泡内部环流和气泡尾部驻涡间的关系。展开更多
The experimental research on cavity flow field plays an important part in the structural design and optimization study of trapped vortex combustor (TVC). Many of the previous flow field experiments were conducted in t...The experimental research on cavity flow field plays an important part in the structural design and optimization study of trapped vortex combustor (TVC). Many of the previous flow field experiments were conducted in the cold condition instead of during combustion. This paper adopting PIV system and Lambda-2 vortex criterion in-vestigates the influence of various factors, such as equivalent ratio in the cavity, air intake parameter in the cavity, mainstream air intake parameter and mainstream holder structure, on cavity flow field for a TVC using methane as the fuel. The experimental research showed that cold-condition flow field differed from the combustion flow field, in terms of either vortex core position or vortex structure. Mainstream air intake velocity and cavity air intake velocity affected the flow field structure. U-type and V-type mainstream holders had significant influence on cavity flow field.展开更多
开展了进口空气马赫数、驻涡区余气系数影响涡轮级间燃烧室燃烧性能的试验研究,获得了燃烧室性能参数的变化规律:随着进口马赫数的增大,总压损失从1.5%增加到7%,流阻系数变化不大,出口温度分布系数OTDF(overall temperature distributio...开展了进口空气马赫数、驻涡区余气系数影响涡轮级间燃烧室燃烧性能的试验研究,获得了燃烧室性能参数的变化规律:随着进口马赫数的增大,总压损失从1.5%增加到7%,流阻系数变化不大,出口温度分布系数OTDF(overall temperature distribution factor)也相应变大;对于不同的进口马赫数,燃烧效率、OTDF随驻涡区余气系数的增大分别为降低和基本不变;燃烧效率大多在70%～85%之间;试验中得到的在燃烧室进口温度为473K时的最大贫油熄火余气系数为9.7.展开更多
文摘The experimental research on cavity flow field plays an important part in the structural design and optimization study of trapped vortex combustor (TVC). Many of the previous flow field experiments were conducted in the cold condition instead of during combustion. This paper adopting PIV system and Lambda-2 vortex criterion in-vestigates the influence of various factors, such as equivalent ratio in the cavity, air intake parameter in the cavity, mainstream air intake parameter and mainstream holder structure, on cavity flow field for a TVC using methane as the fuel. The experimental research showed that cold-condition flow field differed from the combustion flow field, in terms of either vortex core position or vortex structure. Mainstream air intake velocity and cavity air intake velocity affected the flow field structure. U-type and V-type mainstream holders had significant influence on cavity flow field.
文摘开展了进口空气马赫数、驻涡区余气系数影响涡轮级间燃烧室燃烧性能的试验研究,获得了燃烧室性能参数的变化规律:随着进口马赫数的增大,总压损失从1.5%增加到7%,流阻系数变化不大,出口温度分布系数OTDF(overall temperature distribution factor)也相应变大;对于不同的进口马赫数,燃烧效率、OTDF随驻涡区余气系数的增大分别为降低和基本不变;燃烧效率大多在70%～85%之间;试验中得到的在燃烧室进口温度为473K时的最大贫油熄火余气系数为9.7.
