Description
Areas of application
- Density analysis: Precise measurement of three-dimensional density distributions in gases.
- Temperature calculation: Derivation of temperature distributions by combining density measurements and pressure data with the ideal gas equation.
Functionality and advantages
- Working principle: BOS is based on the deflection of light beams by density gradients in the gas. These cause visible shifts in a randomly structured dot pattern that serves as a background.
- Procedure: A reference image without a measurement object is compared with a measurement image of the density field. The shifts are analyzed using cross-correlation algorithms to determine the refractive index.
- 3D density distributions: Tomographic algorithms and the Gladstone-Dale relationship enable the reconstruction of the three-dimensional density field.
- Advantages: Simple implementation, cost-efficient components, can be used with a wide variety of gases and geometries.
Technical details
- Background: Randomly distributed dot pattern for optical analyses.
- Camera system: High-resolution recording of reference and measurement images.
- Computational method: Cross-correlation algorithms for point displacement analysis followed by tomographic back projections for three-dimensional density information.
- Advanced applications: Combination with pressure measurements allows temperature determinations through the ideal gas equation.
