Microwave measurement of phase equilibria

摘要

A microwave resonator apparatus (35) includes a microwave resonant cavity (36) in fluid communication chamber (38) are dimensioned to ensure high attenuation of resonant electromagnetic fields without impeding fluid flow. The resonant properties of the cavity (36) are therefore completely insensitive to variations in the volume of the pressure chamber (38). The resonator has a specialised reentrant geometry. Consequently, two of the cavity's resonant modes depend sensitively upon the formation and volume of any liquid phase present in the cavity. The apparatus and the method are suitable for measuring dielectric properties and phase envelope of fluid mixtures (such as a gas condensate fluid). The apparatus can be used for making several phase envelope measurements without risk of contamination.