论文部分内容阅读
为研究逆向喷流对超声速球头体减阻的影响,该文结合标准k-ε湍流模型,通过求解轴对称和三维Navier-Stokes方程,数值模拟了超声速球头体逆向冷喷流流场,着重分析了喷口总压、喷口尺寸及攻角对流场模态和减阻效果的影响。计算结果显示:喷流能使球头体受到的阻力明显减小;随着喷流总压的增大,在不同喷口尺寸和攻角下,流场均先后经历长射流和短射流穿透模态;存在最大减阻临界喷流总压值,该值与喷口尺寸比呈近似的线性关系,在所研究参数范围内最大减阻可达54.7%;随着攻角的增大,流场的不对称性加强,减阻效果下降。该文的研究对超声速钝体减阻技术在工程上的应用具有一定的参考价值。
In order to study the effect of reverse jet on the drag reduction of supersonic capillaries, a numerical simulation of the reverse jet flow field of the supersonic capillaries was carried out by solving the axisymmetric and three-dimensional Navier-Stokes equations with the standard k-ε turbulence model. The influence of the total pressure at the nozzle, the size of the nozzle and the angle of attack on the mode of the flow field and the drag reduction effect are analyzed emphatically. The calculated results show that the jet head can significantly reduce the resistance of the ball head body. With the increase of the total jet pressure, the jet flow undergoes long jets and short jets at different nozzle sizes and angles of attack State. There is a maximum pressure drop across the critical jet pressure, which is approximately linear with the orifice size ratio. The maximum drag reduction in the range of studied parameters is 54.7%. With the increase of the angle of attack, Asymmetry strengthened, drag reduction effect decreased. The research of this paper has a certain reference value to the application of supersonic bluff body drag reduction technology in engineering.