论文部分内容阅读
计算了欠膨胀状态、设计状态和过膨胀状态三种典型流动状态下的轴对称收扩喷管在3~5μm波段的喷流红外辐射传输特性,并对三种状态的计算结果进行了分析比较。流场采用有限体积法和重整化群(RNG)k-ε湍流模型求解N-S方程得到,喷流的红外辐射强度采用有限体积法结合窄带模型求解吸收发射性介质辐射传输方程得到。计算结果显示:欠膨胀状态的喷流红外辐射强度最大,设计状态与过膨胀状态的喷流红外辐射依次降低,随天顶角的增大差距增大,这与喷流的流动特点有关,说明喷流流动特点的改变影响红外辐射的大小,通过控制喷流的流动可以控制喷流红外辐射强度。
The transmission characteristics of jet flow infrared radiation of axisymmetric convergent and divergent nozzle in three typical flow states of under-expanded state, designed state and over-inflated state were calculated, and the calculation results of the three states were analyzed and compared . The flow field is obtained by solving the N-S equation using the finite volume method and the renormalization group (RNG) k-ε turbulence model. The intensity of the infrared radiation of the jet is obtained by using the finite volume method combined with the narrow-band model to solve the absorption emission radiative transfer equation. The calculated results show that the intensity of infra-red radiation in the inflated state is the largest, and the infra-red infrared radiation in the design state and the over-inflated state decreases in turn, and the gap increases with the increase of the zenith angle, which is related to the jet flow characteristics. Changes in jet flow characteristics of the impact of the size of the infrared radiation, by controlling the jet flow can control jet infrared radiation intensity.