LOX Venturi Flow Meter

This custom machined venturi flow meter is used to measure the flow rate of liquid oxygen (LOX) into our engines. A venturi flow meter works by measuring the pressure differential between the inlet and throat. With known cross-sectional areas and pressures at those two locations the volumetric flow rate through the venturi can be calculated using Bernoulli’s principle. The density of the liquid oxygen is also known from the pressure and temperature of the fluid, allowing us to get accurate mass flow measurements which are critical for characterizing the performance of our rocket engines.

The cross section shows how liquid oxygen flows from left to right - the inlet and throat diameters are varied to create a pressure difference between the two locations measured by the two ports on top, and the port on the bottom measures temperature.

The venturi is frosted over right after testing with cryogenic fluid on our Helluva Engine Test Stand (HETS).