Non-Dimensionalization Challenges in Hypersonic Intake Flow Separation Visualization

 There are a couple of reasons why non-dimensionalizing your hypersonic intake geometry might affect the captured flow pattern with flow separation in your streamtrace:

1. Scaling Effects:

• Non-dimensionalization involves scaling the governing equations of fluid flow using characteristic quantities like reference velocity, length, and pressure. This can sometimes mask the effects of viscosity, which play a crucial role in boundary layers and flow separation.
• In hypersonic flows, where the inertial forces are dominant compared to viscous forces, these effects might be less pronounced. However, they can still influence the formation and size of separation regions.

2. Software Implementation:

• Some CFD (Computational Fluid Dynamics) software might handle non-dimensionalization internally within the solver. If this is the case, the visualization tools like streamtrace might not directly reflect the non-dimensional quantities used in the calculations.
• The software might be displaying the dimensional values (original units) in the streamtrace, even though the calculations are performed using non-dimensional parameters.

3. Interpretation of Streamtrace:

• Streamtrace visualizes the path that a fluid particle would take over time. In a non-dimensionalized simulation, the streamlines might appear "stretched" or "compressed" compared to the dimensional case, even though the underlying flow physics might be similar.

Here's what you can do to investigate the issue further:

• Consult Software Documentation: Check your CFD software's documentation to understand how it handles non-dimensionalization and how it presents results in visualization tools like streamtrace.
• Dimensional vs. Non-Dimensional Results: Try running the simulation with and without non-dimensionalization. Compare the pressure or velocity contours from both simulations to see if the overall flow patterns and separation regions are qualitatively similar.
• Focus on Qualitative Trends: While the exact size and location of the separation region might differ between dimensional and non-dimensional simulations, focus on the overall trend of flow separation and its impact on the performance of the intake.
• Advanced Visualization Techniques: Consider using other visualization techniques alongside streamtrace, such as pressure contours or velocity magnitude plots, to gain a more comprehensive understanding of the flow behavior with and without non-dimensionalization.

By investigating these aspects, you can gain a deeper understanding of how non-dimensionalization affects the visualization of flow separation in your hypersonic intake simulation. Remember, non-dimensionalization is a powerful tool for analyzing flow behavior, but it's important to be aware of its limitations and how it might impact the interpretation of results.