While shooting some IR temp readings the other day, I noticed some interesting effects inside the firebox when the wimpy red laser beam interacted with the "smoke particles" (I call it "soon to be burnt fuel"). Thinking that my green laser pointer might be even more interesting I proceeded to try it out. Here are some observations followed by a link to a YouTube video I uploaded:
1) Even areas that appear to be smoke free are really loaded with unburnt particles. While a green laser beam can be seen in dark conditions due to dust and Rayleigh scattering, the air in the firebox is so full of particles, it can be seen quite easily from any angle and with bright flames competing with it.
2) Some parts of the beam can become clear, indicating that the particles are not present. I'm not sure if they have been consumed (it's often where active flames are located) or the particle laden air has been displaced by air that is actively supporting combustion. It's also noticeable near the air inlets. One could probably use this technique to determine the flow of air in the air-wash system. Would probably be better with a spinning beam to show more volume at once.
3) It's fun to burn wood and play with lasers!
In the video, the laser beam has two bright spots. The one on the right is where the beam is hitting the glass. You might also notice some other bright spots occasionally. They are either double reflections off the wall behind the camera or perhaps some reflected laser light was hitting the camera sensor at times.
1) Even areas that appear to be smoke free are really loaded with unburnt particles. While a green laser beam can be seen in dark conditions due to dust and Rayleigh scattering, the air in the firebox is so full of particles, it can be seen quite easily from any angle and with bright flames competing with it.
2) Some parts of the beam can become clear, indicating that the particles are not present. I'm not sure if they have been consumed (it's often where active flames are located) or the particle laden air has been displaced by air that is actively supporting combustion. It's also noticeable near the air inlets. One could probably use this technique to determine the flow of air in the air-wash system. Would probably be better with a spinning beam to show more volume at once.
3) It's fun to burn wood and play with lasers!
In the video, the laser beam has two bright spots. The one on the right is where the beam is hitting the glass. You might also notice some other bright spots occasionally. They are either double reflections off the wall behind the camera or perhaps some reflected laser light was hitting the camera sensor at times.
