原文传递
Experimental Visualizations of a Generic Launch Vehicle Flow Field: Time-Resolved Shadowgraph and Infrared Imaging.
| 题名： | Experimental Visualizations of a Generic Launch Vehicle Flow Field: Time-Resolved Shadowgraph and Infrared Imaging. |
| 作者： | Garbeff, T. J. I.; Panda, J.; Ross, J. C. |
| 关键词： | Aircraft wakes, Flow distribution, Infrared imagery, Launch vehicles, Mach number, Pressure sensitive paints, Shadowgraph photography, Steady state, Wind tunnel tests, Computational fluid dynamics, Data processing, Surface treatment, Turbulent boundary layer, Turbulent wakes, Unsteady state |
| 摘要： | Time-Resolved shadowgraph and infrared (IR) imaging were performed to investigate off-body and on-body flow features of a generic, 'hammer-head' launch vehicle geometry previously tested by Coe and Nute (1962). The measurements discussed here were one part of a large range of wind tunnel test techniques that included steady-state pressure sensitive paint (PSP), dynamic PSP, unsteady surface pressures, and unsteady force measurements. Image data was captured over a Mach number range of 0.6 less than or equal to M less than or equal to 1.2 at a Reynolds number of 3 million per foot. Both shadowgraph and IR imagery were captured in conjunction with unsteady pressures and forces and correlated with IRIG-B timing. High-speed shadowgraph imagery was used to identify wake structure and reattachment behind the payload fairing of the vehicle. Various data processing strategies were employed and ultimately these results correlated well with the location and magnitude of unsteady surface pressure measurements. Two research grade IR cameras were positioned to image boundary layer transition at the vehicle nose and flow reattachment behind the payload fairing. The poor emissivity of the model surface treatment (fast PSP) proved to be challenging for the infrared measurement. Reference image subtraction and contrast limited adaptive histogram equalization (CLAHE) were used to analyze this dataset. Ultimately turbulent boundary layer transition was observed and located forward of the trip dot line at the model sphere-cone junction. Flow reattachment location was identified behind the payload fairing in both steady and unsteady thermal data. As demonstrated in this effort, recent advances in high-speed and thermal imaging technology have modernized classical techniques providing a new viewpoint for the modern researcher |
| 报告类型： | 科技报告 |
相关文献
- Performance Analysis of Tower Watch Camera Systems; Final rept
- Imaging Study for Small Unmanned Aerial Vehicle (UAV)-Mounted Ground-Penetrating Radar: Part 1 - Methodology and Analytic Formulation.
- In-Flight Boundary-Layer Transition on a Large Flat Plate at Supersonic Speeds.
- In-Flight Boundary-Layer Transition on a Large Flat Plate at Supersonic Speeds.
- Best Practices for the Application of Functional Near Infrared Spectroscopy to Operator State Sensing.
- ADVANCED TECHNIQUES FOR TRAVEL TIME DATA COLLECTION.
检索历史
应用推荐
