Method and device for measuring the viscosity of a flowing fluid
OwnerAnders Noreninventor
Life of this patent
Estimating the term…
Abstract
A device for measuring the viscosity of the fluid flowing in a closed passage includes a rotor whose speed of rotation is directly dependent on the rate of flow of the fluid. The rotor is connected to an activatable and deactivatable brake means which has an adjustable braking force. Depending on the setting of the brake means, the brake is operative to cause a greater or smaller lag in the rotary speed of the rotor in relation to an unbraked rotor or a rotor braked with a smaller force. The measuring means is operative to determine the resultant different rotational speeds of the rotor and the different in these speeds is a measurement of viscosity.
Claims11
A device for determining the viscosity of a fluid flowing in a closed passage, said device comprising:
- a rotor which, in use of the device, is surrounded by the fluid and the speed of rotation of which is directly dependent on the flow rate of the fluid, said rotor being carried symmetrically by a shaft which extends substantially at right angles to the longitudinal axis of the passage, said rotor shaft being located asymmetrically in relation to the longitudinal axis of said passage so that when fluid flows at constant velocity through the conduit the rotor will rotate at constant velocity, said rotor having the form of circular plate or cylinder;
- brake means for applying a braking force to the rotor, the braking force being sufficient to cause the rotor to rotate at a reduced constant speed in relation to the constant speed of an unbraked rotor or of a rotor braked with a smaller braking force;
- and
- rotational speed measuring means for measuring the resulting different constant rotational speeds of the rotor, a difference in said constant rotational speeds being representative of the viscosity of the fluid.
A method of determining the viscosity of a fluid flowing in a closed passage which comprises:
- (a) providing a rotor which is surrounded by the fluid in said passage, the speed of rotation of the rotor being directly dependent on the flow rate of the fluid, the rotor being carried symmetrically by a shaft which extends substantially at right angles to the longitudinal axis of the passage, said rotor shaft being located asymmetrically in relation to the longitudinal axis of said passage so that when a fluid flows at constant velocity through the conduit the rotor will rotate at constant velocity, said rotor having the form of a circular plate or cylinder;
- (b) causing a fluid to flow through said passage at an initial constant velocity to cause the rotor to rotate at an initial constant velocity;
- (c) applying a predetermined braking force to the rotor to cause the rotor to rotate at a constant velocity which is reduced in relation to the initial constant velocity;
- and
- (d) determining, from the difference between the initial and reduced constant velocities of the rotor, the viscosity of said fluid.
Dependencies are inferred from the claim text.