I spent a bit time looking for ways to improve oxygen delivery.
This video mentions one way, by adding a small gadget, Oxymizer, with a reservoir to store oxygen that normally goes wasted during exhaling. They claim they can improve flow rate from 3L to that corresponding of 5L. Was this the same idea as you speculated with on how to improve flow rate?
Looks interesting, I wonder how it works; the Oxymizer seems to be used in conjunction with a regular nasal cannula (my oxygen concentrator comes with a nasal cannula, which is what I am using at the moment to breathe in the oxygen). I wonder how the Oxymizer is able to momentarily shut off the oxygen during your exhalation?
When using a
non-rebreather mask you get the same principle of using a reservoir to store oxygen that would normally be wasted when exhaling. A non-rebreather mask has a small plastic bag reservoir, and a set of one-way valves to ensure when you breathe in, it takes the oxygen from the reservoir bag, and when you breathe out, it directs your breath out of the mask.
I bought a non-rebreather mask, but it is so cheaply made that I does not seem to work properly (it does not fit snuggly to the face for one thing, so there are leaks). I can't see to find a high quality non-rebreather mask for sale.
My idea for converting the oxygen concentrator machine to supplying 90% oxygen at 6 liters per minute is simply to use a very large reservoir plastic bag, of around a third of a cubic meter in volume, and to let the machine run for several hours to fill up this large reservoir bag before you start breathing the oxygen. So you fill this large reservoir with 90% oxygen, and then when filled, you connect your non-rebreather mask to the large reservoir, so that you are breathing in 90% oxygen.
Since the normal human breathing rate at rest is around 6 liters per minute, in order to have enough oxygen to last for a session of 60 minutes, you would need a reservoir bag with a 60 x 6 = 360 liters capacity. And you would need to run the oxygen concentrator machine for 6 hours beforehand to fill this reservoir, since my machine delivers 1 liter of 90% oxygen per minute.
Or if you want to breathe 70% oxygen (which my machine delivers at 2 liters per minute), then you only need to run the machine for 3 hours beforehand.
The only potential issue I can see with this setup is that oxygen can slowly diffuse through thin materials like plastic bags, so after some hours you may lose a bit of your oxygen in the reservoir bag. But if this is a problem, it will be less of an issue if you use 70% oxygen, which is only stored for 3 hours before use.
