This paper presents a detailed investigation of unsteady supersonic flows around a typical two-body configuration, which consists of a capsule and a canopy. The cases with different trailing distances between the caps...This paper presents a detailed investigation of unsteady supersonic flows around a typical two-body configuration, which consists of a capsule and a canopy. The cases with different trailing distances between the capsule and canopy are simulated. The objective of this study is to examine the detailed effects of trailing distance on the flow fields and analyze the flow physics of the different flow modes around the parachute-like two-body model. The computational results show unsteady pulsating flow fields in the small trailing distance cases and are in reasonable agree- ment with the experimental data. As the trailing distance increases, this unsteady flow mode takes different forms along with the wake/shock and shock/shock interactions, and then gradually fades away and transits to oscillate mode, which is very different from the former. As the trailing distance keeps increasing, only the capsule wake/canopy shock interaction is present in the flow field around the two-body model, which reveals that the unsteady capsule shock/canopy shock interaction is a key mechanism for the pulsation mode.展开更多
When measurements are performed in high speed, small-scale compressors, the use of curved glasswindows is required in order to avoid any mismatch between the measurement window and the casing. However, the glass curva...When measurements are performed in high speed, small-scale compressors, the use of curved glasswindows is required in order to avoid any mismatch between the measurement window and the casing. However, the glass curvature leads to optical distortions, which hinder acceptable measurementsand can even prevent the acquisition of any data. Thus, an original optical assembly, which consistsin inserting a simple and inexpensive corrective window between the frontal lens of the anemometerand the shroud window, is proposed. The way of determining the geometric characteristics and theposition of this corrective window, which restores very acceptable fool, is presented in the paper. Thereliability of this corrective optical assembly is highlighted by comparative measurements in a test case.Using such an optical setting, L2F measurements were realized along a section, downstream of the inletguide vane (IGV) of a transonic compressor stage. The spatial resolution leads to a good descriptionof the interaction of the wake with the oblique shock emanating from the leading edge of the rotor.A phenomenological study of the wake/shock interaction with a change of frame is realized using thestreamwise equation of the transport of vorticity.展开更多
基金supported by the National Natural Science Foundation of China(No.11702332)
文摘This paper presents a detailed investigation of unsteady supersonic flows around a typical two-body configuration, which consists of a capsule and a canopy. The cases with different trailing distances between the capsule and canopy are simulated. The objective of this study is to examine the detailed effects of trailing distance on the flow fields and analyze the flow physics of the different flow modes around the parachute-like two-body model. The computational results show unsteady pulsating flow fields in the small trailing distance cases and are in reasonable agree- ment with the experimental data. As the trailing distance increases, this unsteady flow mode takes different forms along with the wake/shock and shock/shock interactions, and then gradually fades away and transits to oscillate mode, which is very different from the former. As the trailing distance keeps increasing, only the capsule wake/canopy shock interaction is present in the flow field around the two-body model, which reveals that the unsteady capsule shock/canopy shock interaction is a key mechanism for the pulsation mode.
文摘When measurements are performed in high speed, small-scale compressors, the use of curved glasswindows is required in order to avoid any mismatch between the measurement window and the casing. However, the glass curvature leads to optical distortions, which hinder acceptable measurementsand can even prevent the acquisition of any data. Thus, an original optical assembly, which consistsin inserting a simple and inexpensive corrective window between the frontal lens of the anemometerand the shroud window, is proposed. The way of determining the geometric characteristics and theposition of this corrective window, which restores very acceptable fool, is presented in the paper. Thereliability of this corrective optical assembly is highlighted by comparative measurements in a test case.Using such an optical setting, L2F measurements were realized along a section, downstream of the inletguide vane (IGV) of a transonic compressor stage. The spatial resolution leads to a good descriptionof the interaction of the wake with the oblique shock emanating from the leading edge of the rotor.A phenomenological study of the wake/shock interaction with a change of frame is realized using thestreamwise equation of the transport of vorticity.
