capillarityrheometria

Capillarityrheometria is a technique used to study the rheological properties of fluids, particularly those with low viscosity, by observing their flow through capillary tubes. This method relies on the precise measurement of pressure drop across a known length of capillary as a function of flow rate. By analyzing these relationships, researchers can determine key rheological parameters such as viscosity, yield stress, and viscoelasticity.

The fundamental principle behind capillarityrheometria is Poiseuille's Law, which describes laminar flow of a Newtonian fluid through a cylindrical tube. Deviations from this ideal behavior indicate non-Newtonian characteristics. The technique involves forcing the fluid through a capillary with a carefully controlled pressure or flow rate, and measuring the corresponding flow rate or pressure, respectively. The geometry of the capillary, including its diameter and length, is critical for accurate calculations.

This method is particularly advantageous for small sample volumes and can be adapted for a wide range of fluids, including solutions, suspensions, emulsions, and gels. It is sensitive to subtle changes in fluid structure and is often employed in research and development to characterize new materials, study phase transitions, and monitor the stability of complex fluids. Applications span various fields, including food science, pharmaceuticals, cosmetics, and materials science.