A novel fluid dynamic inline viscometer suitable for harsh process conditions

Abstract

Process viscometers have important applications in real-time quality and process control for a wide range of industrial processes, e.g. in the food, chemical, pharmaceutical, and petrochemical industries. Established commercial instruments like rotational, vibrating, and tube viscometers can suffer from poor lifetime or insufficient performance in harsh applications. This contribution introduces a novel process viscometer based on a fluid dynamic measurement principle. The pressure building up by the process fluid being forced through a tapered gap is used to displace a spring-type structure. This displacement is measured with a resonant inductive sensor and is strictly proportional to the dynamic viscosity of the fluid. The measurement principle and construction of the instrument allow its use under harsh process conditions such as high pressure and temperature variations and with abrasive and inhomogeneous fluids and suspensions while maintaining excellent repeatability.