Prototypes and study techniques specially developed by Lab FIRP at the request of partners, for research and development.
Foam column at high pressure high temperature
The FIRP Laboratory has been studying foaming phenomena for about 10 years, but always in conditions of temperature and pressure close to ambient. In certain cases, it is necessary to estimate the foamability and stability of foams under conditions of very severe temperature and pressure. This is the case of the injection of foaming fluids in oil fields, either as horizontal drilling mud or as plugging fluid. To support the projects-agreements, the FIRP Lab has developed a foam column that can work at high pressure and high temperature.
The equipment consists of a vertical column similar to the classic Bikerman apparatus, in which a gas is bubbled through a small volume of liquid. Foam forms at the bottom and breaks at the top, eventually reaching equilibrium or producing pulsations. Once the foam is formed, the gas flow is stopped and the rate of collapse begins to be measured, which provides information on stability. In all cases the experimental problem is to detect the height of the foam as a function of time, which is generally done by visual observation. In the case of a confined fluid and at high pressure and temperature, it is necessary to have another means of detecting the level of the foam column. The Confined Foam Column is a metal cylinder on the wall of which more than a hundred infrared detectors have been placed, located in a double helix, one for the emitters and the other for the detectors. The signals from these detectors are collected by a data acquisition system and processed to provide the foam level variation in real time through an application programmed in Labview® (National Instruments).
Rolling sphere viscometer for opaque fluids
The FIRP Lab has developed a Rolling Sphere Viscometer for the evaluation of the viscous characteristics of opaque fluids confined in a hermetically closed area, with the intention that it can eventually be adapted to carry out measurements under high temperature and high pressure conditions. The purpose of the team is to evaluate the rheology of drilling fluids such as muds, polymeric gels or foams, within the framework of agreements with industrial partners.
The measuring principle of the equipment is that of the conventional ball viscometer, in which a heavy sphere is dropped through a fluid confined within a rigid and inclined tube. The measurement of the travel time of the sphere makes it possible to estimate the viscosity of the fluid, or in any case to establish a parameter indicative of the resistance to flow. By varying the diameter of the sphere and the angle of inclination of the tube, it is possible to modify the shear rate to which the fluid is subjected, that is, the measuring range. The movement of the metallic sphere is detected by an electrical-inductive type system comprising ten coils wound along the tube, equidistant from each other and connected in series.
Once conditioned, the signal passes to a data acquisition system, after which it can be processed to determine the rate of fall of the sphere and rheological parameters such as apparent viscosity and equivalent shear rate. The viscometer developed is inexpensive and potentially more flexible than a concentric cylinder rheometer, since it can be adapted to operate with continuous fluid feed.
The equipment seems well adapted to the study of rheologically complex fluids, especially pseudoplastic fluids with a certain degree of thixotropy.