Benchmarking background oriented schlieren against interferometric measurement using open source tools

Area of Science:

• Fluid dynamics
• Optical diagnostics

Background:

• Under-expanded jets are crucial in various aerospace and industrial applications.
• Accurate measurement of gas density distribution is essential for understanding jet behavior.

Purpose of the Study:

• To measure gas flow from an under-expanding jet nozzle.
• To compare density distributions obtained from two different optical diagnostic techniques.

Main Methods:

• Utilized synchronized background oriented schlieren (BOS) and interferometry.
• Obtained gas density distribution from BOS shift vector fields.
• Employed a simple calibration routine and open-source Python recipes for data comparison.

Main Results:

• Successfully obtained gas density distribution using BOS.
• Demonstrated good agreement between density distributions from BOS and interferometry.
• Validated the effectiveness of the combined diagnostic approach.

Conclusions:

• Synchronized BOS and interferometry provide a robust method for measuring gas density in under-expanded jets.
• Open-source Python tools facilitate efficient data processing and comparison.
• The study validates a cost-effective approach for flow diagnostics.