How To See Air Currents

TL;DR

Schlieren photography uses a concave parabolic mirror, LED light source, razor blade, and camera lens to capture the visual effects of invisible air currents, temperature differences, and composition changes in the air.

Transcript

If there were a portal through which you could see all of the invisible air currents, temperature gradients and differences in pressure and composition of air, then this is what it would look like to strike a match. This is helium being squeezed out of a balloon. You could see the warm air rising off your hands. The invisible vapors of isopropyl al... Read More

Key Insights

• 🙂 Schlieren photography uses a combination of reflective and refractive properties of light to capture invisible phenomena.
• 🙂 The setup includes a concave parabolic mirror, LED light source, razor blade, and camera lens.
• 🫥 Variations in refractive index caused by temperature differences and different substances result in visible effects in the images.
• 💐 Schlieren photography has applications in studying aerodynamics, fluid flow, and pressure differences.

Questions & Answers

Q: How does Schlieren photography work?

Schlieren photography works by using reflective and refractive properties of light to capture the effects of air currents and temperature differences. The setup involves a concave parabolic mirror, LED light source, razor blade, and camera lens.

Q: What can be achieved with Schlieren photography?

With Schlieren photography, we can visualize phenomena such as heat rising off a candle, breath being exhaled, and cold air being poured out of a cup of ice. It can also show the effects of gas emissions from a lighter and the refraction of light passing through a bubble.

Q: How does the refractive index affect Schlieren photography?

The refractive index of a material determines how light travels through it. In Schlieren photography, variations in refractive index, caused by temperature differences or different substances, result in deflections of light and the formation of bright and dark spots in the captured image.

Q: What applications does Schlieren photography have?

Schlieren photography has been used to study aerodynamics, fluid flow, and pressure differences. It allows researchers to visualize shockwaves, temperature gradients, and changes in gas composition. It has also been used historically to detect defects in lens glass.

Summary & Key Takeaways

• Schlieren photography reveals normally invisible air currents, temperature gradients, and differences in the composition of air.

• This technique involves the use of a concave parabolic mirror, LED light source, razor blade, and camera lens.

• By capturing the reflections and refractions of light, Schlieren photography allows us to see heat, breath, and even gas emissions.