A density and viscosity sensor

Abstract

A density and viscosity sensor 1 for measuring density and viscosity of fluid F, the sensor 1 comprising a resonating element 3, 3A, 3B, 3C, 3D arranged to be immersed in the fluid F, an actuating / detecting element 4A, 4B coupled to the resonating element, and a connector 7 for coupling to the actuating / detecting element 4A, 4B. The sensor 1 further comprises a housing 2 defining a chamber 8A isolated from the fluid F, the housing 2 comprising an area of reduced thickness defining a membrane 9 separating the chamber 8A from the fluid F. The actuating / detecting element 4A, 4B is positioned within the chamber so as to be isolated from the fluid F and mechanically coupled to the membrane 9. The resonating element 3, 3A, 3B, 3C, 3D arranged to be immersed in the fluid F is mechanically coupled to the membrane 9. The membrane 9 has a thickness enabling transfer of mechanical vibration between the actuating / detecting element 4A, 4B and the resonating element 3, 3A, 3B, 3C, 3D.

Description

technical field [0001] The present invention relates to sensors for measuring the density and viscosity of fluids. The sensor is based on the use of mechanical elements placed in vibrations of the measured fluid. [0002] The invention is applicable to the measurement of density and viscosity in oilfield field, chemical industry, food field and the like. Background technique [0003] Density is a measure of the mass per unit volume of a medium. The SI unit of density is the kilogram per cubic meter (kg / m 3 ). For example, under standard temperature and pressure conditions, the densities of water and ethyl alcohol are 1000kg / m3 respectively 3 and 790kg / m 3 . [0004] Viscosity is a measure of a fluid's resistance to deformation under shear stress. Viscosity describes a fluid's internal resistance to flow and can be thought of as a measure of fluid friction. The international standard physical unit of dynamic viscosity is Pascal second (Pa.S). The centimeter-gram-seco...

AI Technical Summary

Problems solved by technology

[0006] The typical size of this transducer is a few centimeters, requiring a large and expensive sensor housing

This makes the measurement setup highly invasive, hindering its use in small sample chambers or small pipes

In addition, due to the large size, it becomes very difficult to operate at high pressure and high temperature

Images