My target is to create a valve with multiple inlet capillaries. And my output is a pipe of a larger diameter. I do not want to use any electrical systems, and at the same time, I want to maintain enough negative pressure inside the valve to influence the flow of fluid to be from capillaries to the pipe and not the other way round. The pipe-capillary system is evacuated and the fluid inside is at a higher than atmospheric pressure (we can assume 4-5 atm). I also wish the flow to remain laminar and avoid turbulence.
I looked into kinds of pumps which, in principle, achieve this... But I could not find any self-controlling system which does not require external power to maintain the pressure force required. Pneumatic systems like the flow valve looked promising but I could not figure out a way to achieve the requirement I am aiming for. I was thinking of inserting a high pressured section inside the valve which would push a diaphragm with constant force. And that force can be used to maintain the negative pressure that I want. Another idea with having a vacuum instead of a high-pressure fluid to achieve the same (effectively the inverse mechanism). But from a design perspective, I could not figure out a way to avoid leakage of the high pressure over time. My idea was inspired by the action of a syringe. I tried to design a CAD model for the same to simulate it... But could not figure out how to implement all that I read on this topic.
Does a valve or pneumatic system exist that achieves this (am I missing some information that I should know)? And if not, how can I make such a valve? I need to manufacture this as well, so simplicity/availability of resources is important. But any theoretically sound solution will also be greatly appreciated :)
Thanks in advance