The history of the rotary viscometer

Introduction
With the development of science and the improvement of industrial production, the determination of the viscosity of substances has become very important. Rotational viscometers can be used to determine the viscosity and flow behavior of polymer liquids. Because most polymers are processed under viscous flow conditions, for the determination of polymer viscosity, it is very important to grasp the performance laws of viscous flow in the polymer production process.
Existing rotational viscometers mainly include tumbler type, cone-plate type and parallel plate type viscometers.
Rotary viscometer is used to measure the viscous resistance and dynamic viscosity of liquids. It is widely used to measure the viscosity of various fluids such as grease, paint, plastics, food, medicine, cosmetics, and adhesive products.

history
The rotational viscosity measurement method pioneered by the Brookfield family in the United States uses its unique relationship between the shear and resistance generated by the rotor and the fluid to obtain a brand-new viscosity value, creating a precedent for the measurement of dynamic viscosity. The Brookfield family designed a dynamic viscosity measuring instrument in the world under the name of its own family, that is, a rotational viscosity measuring instrument, which is today's Brookfield viscometer. And Brinell is also a shorthand for the Brookfield family.
Starting from the dial-type viscometer, the rotational viscometer has undergone 75 years of transformation and upgrading, and its performance is getting better and better. Later, the digital display viscometers DV-I, DV-II, and DV-III gradually appear in the viscosity. Great progress has been made in measurement. This makes viscosity measurement not only a simple measurement of viscosity, but also other properties of the fluid, such as thixotropy.
Later, the rotary viscometer entered the Chinese market and played a significant role in the development of my country's polymer industry.

Drum viscometer
This viscometer, as its name suggests, is a flat-bottomed cylinder on the outside, with a cylinder in the coaxial center. There are two slits formed by parallel surfaces between the cylinder and the slit, and the polymer liquid is located in the slit. The cylinder is driven by the stepless speed regulator to make the cylinder rotate. The cylinder is suspended on a force measuring device and connected to it by a spring. When the cylinder rotates, the polymer liquid in the slit flows due to the shearing action. The viscous body fluid drives the cylinder to rotate until the cylinder's torque balances with the spring force and stops rotating. At this time, the circle The cylinder rotates by a certain angle θ. At equilibrium, the shearing action of the liquid has also reached a stable state, and then through the torque of the cylinder and the rotation speed of the cylinder, the shear force and shear rate at each position in the annular seam can be calculated by formulas.