System and method for estimating apparent viscosity of a non-newtonian fluid
AssigneeLincoln Industrial Corporation
InventorsCanlong He, Paul G. Conley
Life of this patent
Estimating the term…
Abstract
Method and apparatus for estimating an apparent viscosity of a non-Newtonian fluid. The results may be used for selecting equipment for pumping systems.
Claims30
A method of estimating an apparent viscosity of a non-Newtonian fluid by using test apparatus, said test apparatus comprising a conduit for receiving said fluid under pressure, said conduit having an inside diameter D, a length L and a L/D ratio greater than 40, a valve system operable in a first mode to block fluid flow in the conduit to allow fluid to accumulate under pressure in a pressure zone of the conduit and in a second mode to vent the pressure zone of the conduit, and a pressure measuring device for measuring the pressure inside the pressure zone of the conduit, said method comprising:
- a) with said valve system operating in its first mode, supplying fluid under pressure to said conduit until the fluid in said pressure zone reaches a predetermined pressure;
- b) operating said valve system in its second mode to vent the pressure zone of the conduit for a predetermined time interval during which there is a transition between non-Newtonian flow and Newtonian flow;
- c) using said pressure measuring device, measuring the pressure P in said pressure zone during said transition;
- d) calculating a wall shear stress τ of the fluid based on the conduit length L, the conduit diameter D, and the measured pressure P during said transition;
- and
- e) determining an estimated apparent viscosity ηest of the fluid at a selected shear rate using a first formula ηest=τ/γs, where τ is said calculated wall shear stress and γs is the selected shear rate not based on any measurement of fluid output from the conduit.
A method of selecting equipment for a system for pumping a non-Newtonian fluid, comprising:
- a) providing test apparatus comprising a conduit for receiving said fluid under pressure, said conduit having an inside diameter D, a length L and a L/D ratio greater than 40, a valve system operable in a first mode to block fluid flow in the conduit to allow fluid to accumulate in a second mode to vent the pressure zone of the conduit, and a pressure measuring device for measuring the pressure inside the pressure zone of the conduit;
- b) with said valve system operating in its first mode, supplying fluid under pressure to said conduit until the fluid in said pressure zone reaches a predetermined pressure;
- c) operating said valve system in its second mode to vent the pressure zone of the conduit for a predetermined time interval during which there is a transition between non-Newtonian flow and Newtonian flow;
- d) using said pressure measuring device, measuring the pressure P in said pressure zone during said transition;
- e) calculating a wall shear stress τ of the fluid based on conduit length L, conduit diameter D, and the measured pressure P during said transition;
- f) determining an estimated apparent viscosity ηest of the fluid at a selected shear rate using a first formula ηest=τ/γs, where τ is said calculated wall shear stress and γs is the selected shear rate not based on any measurement of fluid output from the conduit;
- and
- g) selecting equipment for said pumping system based at least in part on said estimated apparent viscosity ηest.
A system for estimating an apparent viscosity of a non-Newtonian fluid comprising:
- a conduit for receiving said fluid under pressure, said conduit having an inside diameter D, a length L and a L/D ratio greater than 40;
- a valve system operable in a first mode to block fluid flow in the conduit to allow fluid to accumulate under pressure in a pressure zone of the conduit and in a second mode to vent the pressure zone of the conduit;
- a pressure measuring device for measuring the pressure inside the pressure zone of the conduit, said pressure measuring device providing a pressure signal indicative of the pressure inside the pressure zone;
- and
- a controller selectively operating said valve system in said first and second modes and receiving the pressure signal,
- said controller providing output information indicative of the viscosity of the fluid based on the conduit length L, the conduit diameter D, and a measured pressure P when the valve mechanism is open and the fluid transitions from non-Newtonian flow to Newtonian flow, and not based on any measurement of fluid output from the conduit.
Dependencies are inferred from the claim text.