HowTo 3: Getting Onion Base Jets and Collisions
Very often there is an image from a dropper where the base of the jet or collision looks like an onion. I was amazed and really liked it very much. But in the early days, I do not know how to do it, or at least do it repeatly.
Then later on, I found out how to do it. Here are the steps:
1. Use a larger opening nozzle, in this tutorial, I used the 8mm OD nozzle (ID is about 5.5 - 5.8mm). This is important
1. Find the FD value when water just hit the surface. Follow tutorial 1 to do so. Record this FD value
3. Set # of drop to 1 and adjust drop size to try to get a jet as tall as possible, like the 1st picture in above. This is the standard exercise shown in tutorial 1 and in user manual
4. Now, keep increasing drop size 5ms at a time. You will notice the jet is actually getting shorter and shorter until certain point it is almost gone like 2nd picture in above.
5. Now keep increasing the drop size, but at finer step, 1ms at a time until you start to hear popping sound from the jet. IMPORTANT note: increase the drop size 1 unit at the time. When the jet with bubble base is tallest, increasing it by 1 unit will completely destroys it.
6. When popping sound gets louder, you will notice that the jet starts to go taller with a large bubble at the base, sort of like 3rd picture above
7. Keep increasing the drop size until you get the tallest jet with bubble base (looks like onion), like the 4th picture. Adjust FD to get the tallest image and record this value.
8. Use the technique outlined in tutorial 1 to set the size of second drop and delay and try to get a collision like 5th and 6th pix above.