论文部分内容阅读
采用三维雷诺平均N-S方程和标准k-ε湍流模型,对不同间隙高度超声速膨胀器的流场和性能进行了数值研究,结果表明:间隙高度显著影响三维流道内的局部流动特性和超声速膨胀器的整体性能,随间隙高度增加,气流最高相对马赫数降低,高速区范围逐步缩小;泄漏涡增强,尺度变大,横向和径向运动明显,泄漏损失增加,但激波及激波附面层相互作用的损失降低;超声速膨胀器的膨胀比先增大后减小,等熵绝热效率持续降低.下端壁、吸力面附近低能流体之间以及与壁面的摩擦损失和间隙泄漏损失是有间隙超声速膨胀器三维流道内损失的主要来源,超声速膨胀器的间隙高度宜在0.9%h0~1.5%h0之间选取.
Three-dimensional Reynolds-averaged Navier-Stokes equations and standard k-ε turbulence model were used to study the numerical simulation of flow field and performance of high-speed supersonic expanders with different clearances. The results show that the clearance height significantly affects the local flow characteristics in the three- The overall performance increases with the height of the gap, the maximum relative Mach number decreases, and the range of the high speed zone decreases gradually. The leakage vortex increases, the scale becomes larger, the horizontal and radial movement are obvious, and the leakage loss increases. However, the interaction between shock and shock The expansion ratio of supersonic expansion device increases firstly and then decreases, and the isentropic adiabatic efficiency continues to decrease.The friction loss and gap leakage loss between the lower end wall, near the suction surface and the wall are interstitial supersonic expander The main source of loss in the three-dimensional flow path, supersonic expander gap height should be selected in 0.9% h0 ~ 1.5% h0.