Abstract: A method to measure both the isothermal secant and tangent bulk modules and the density of functional fluids. The instrumentation and methodology described in this invention use much smaller volumes of fluids which permits the measurement of these critical properties on experimental fluids which are available in only limited quantities.

Abstract: A method is disclosed for determining bulk modulus of a liquid based on a pressure-volume-temperature relationship at constant volume corrected for changes in system volume due to elevated pressure and temperature. The apparatus used to determine bulk modulus comprises a pressure vessel in which the liquid to be tested is introduced, and from which all gases are removed. The vessel is placed in a constant temperature oven and the pressure is recorded. The method for determining bulk modulus and density requires calibration of the vessel volume changs due to pressure and temperature.

Abstract: An automatic oxygen absorption measuring system has a controllable source of pressurized oxygen, a controllable venting device, and a device for indicating incremental gas volume changes connected through a controlled gas reservoir to an oxygen circulating testing section where oxygen is passed through a liquid sample at a fixed temperature. Upon the liberation of other gases than oxygen or absorption of oxygen, the gas pressure changes a liquid fluid level in the device for indicating incremental gas changes. An electronic circuit causes the venting or inputting of gas until an equilibrium pressure is obtained. Each change is noted on a recording device. The device for indicating incremental gas volume changes has two glass bulbs attached in line with a manometer filled with electrically conductive liquid fluid. Four electrical contacts placed about the bulbs indicate the level of the liquid fluid.