Design Parameters for Venturi Tube to Obtain Variable Flow Mix of Air & O2

This is a very specialised field.
I worked on respiratory measuring instruments for several years. I don't think I'd want a studen messing with human ventilation. If you must then it would require an awfull lot of reading of medical journals, standards and such like just to understand the relevant terminology... It is difficult to gain 3years experience over a short project...

Sorry to sound negative, but this is also a field which is (quite rightly) subject to many regulations.
I would suggest finding an alternative project. If you want to play with venturis, maybe look at automatic dosing of detergents int a flow of water for cleaning applictions e.g filling buckets, trigger bottles, or car washing.

Del

Sir,

I am the One who had asked the question to my teacher Mr Patel.

I would like to modify my question and seek your guidance.

Mixing of two gases is possible in a venturi tube having by having slits at the throat. But if there exists some positive pressure at the end ( having larger diameter ), how to get the desired concentration of the driving gas and the Driven gas ?

As I said in #1. I worked in measurement... so gas isn't my field.
I also suggested working with liquids... they are much easier to see, measure, contain, understand etc.(especially if one is brightly coloured)
The ideal project is one which can be broken down into small achievable steps and yet expanded into a meaningful whole.

Del

Ditto on Del's comments. I built a venturi to extract samples of flue gas and it took $5000 of a fluid professor's tutoring and a year or so of experimentation on my part to get it to work. And I still don't know even a tenth of what I would need to work on a patient ventilation device. When my devices didn't work right, it didn't hurt the power plant, but when a ventilator doesn't work right....Double Yoi!

As above... I have completed jobs at a couple of companies who make gas appliances, they use venturies (ii?) for the correct gas / air mix.

Whenever I've asked how they designed the venturi its always been a case of blank faces and a lot of hummming and errrring about "we fiddled until we got it right!!", even admitting that they still didn't know whether they had got it right after 40 years of manufacture!!

In fact I am doing a job at the moment for a well known company that produces tiny jets through which LPG passes into a venturi to mix with air before being burnt - they have no idea who designed it saying that we've always made them that size and shape!!

John (good luck!)

I have the feeling that your student already asked cr4 for this question with an other formulation and because he was send to look at other threads on same subject came to you. There are many discussions on this subject you can find under "venturi".