I need assistance (or experience feedback) in estimating if a Venturi pump would work at low pressure. A boiler under vacuum (10% atmosphere) will produce steam (at a given speed depending on the boiler power) and the steam flow will be used to suck water at the same temperature (of boiling water under this vacuum, about 50 degrees C) and pressure in a Venturi style setup.
From the wiki articles I read about the Venturi tube, the usual equations giving the pressure difference between the constriction and the larger tube are for incompressible fluids. I do worry that 10% ATM steam would be very compressible though. So in short I need an equation for tying up the tube diameters, the steam feed speed, and the suction generated under such conditions