I am looking to design a diaphragm pump for a device. I know that I would need to achieve a (negative) vacuum pressure of ~ 350-400 mmHg. I know from standard rotary pump design the pump rate should be dictated by stroke volume and speed, and assume this is the same for a diaphragm pump, with stroke length perhaps.
How can I calculate the ultimate achievable vacuum pressure? I am looking for an explanation of the idealized equations for calculating this property of a diaphragm pump.
This would be for pumping a water based fluid, although slightly more viscous.