US 9,176,040 B2Granted

Apparatus and method for measuring fluid viscosity

AssigneeChung Yuan Christian University

InventorsHuei Chu Weng, Yuan Kai Kao

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Abstract

An apparatus and a method for measuring fluid viscosity are revealed. An inlet end of a container is larger than an outlet end of the container. A fluid flows through the outlet end at a flow rate. A volume of the fluid flowing out of the outlet end is measured by a graduated cylinder while the time taken for the fluid to flow through the outlet end is measured by a timer. The flow rate is associated with the volume and the time of the fluid and the viscosity of the fluid is obtained according to a density and a pressure gradient of the fluid, an outlet end radius and the flow rate. The apparatus has simple structure, easy operation and maintenance. Moreover, less space is required and the apparatus cost is low. Therefore, the testability is improved, the measurement time is reduced, and the convenience in use is enhanced.

Claims10

Dependent claims

An apparatus for measuring viscosity comprising:

a container having an inlet end and an outlet end, a radius of the inlet end is larger than a radius of the outlet end while the container is a vertical reducer, the container containing a fluid under measuring, the fluid having a density value ρ and a pressure gradient value dp/dz, placed within the container, and flowing out of the outlet end at a flow rate value ;
a pressure controller connected to both the inlet end and the outlet end, and modulating an inlet pressure value of the fluid at the inlet end and modulating an outlet pressure value of the fluid at the outlet end to modulate the pressure gradient value dp/dz of the fluid according to the inlet pressure value, the outlet pressure value and a height of the container;
a graduated cylinder, disposed under the outlet end, for measuring a volume of the fluid flowing out of the outlet end while the fluid is discharged from the outlet end;
and
a timer, measuring a time during the fluid flowing out of the outlet end while the flow rate value is associated with the volume and the time;
a microprocessor that calculates a viscosity value μ of the fluid is defined by following Expression;
μ=π(ρg+dp/dz)γout4/8 Expression 1
where, g is gravity, γout is a radius of the outlet end.

5 more elements

A method for measuring viscosity comprising the steps of:

providing a container, wherein the container is a vertical reducer having an inlet end and an outlet end, a radius of the inlet end is larger than a radius of the outlet end;
using a pressure controller connected with the inlet end and the outlet end to modulate an inlet pressure value of the fluid at the inlet end;
using the pressure controller connected with the inlet end and the outlet end to modulate an outlet pressure value of the fluid at the outlet end;
measuring a height value of the container;
modulating a pressure gradient value dp/dz in accordance with the inlet pressure value, the outlet pressure value and the height value;
flowing the fluid into the container through the inlet end of the container and out of the outlet end of the container;
measuring a volume of the fluid flowing out of the outlet end and a time during the fluid flowing out of the outlet end while a flow rate value of the fluid flowing out of the outlet end is associated with the volume and the time;
and
using a microprocessor calculating and obtaining a viscosity value μ of the fluid according to a density value ρ of the fluid times acceleration, and the viscosity value μ is defined by following Expression 1:
μ=π(ρg+dp/dz)γout4/8 Expression 1
where, g is gravity, γout is a radius of the outlet end.

8 more elements

Dependencies are inferred from the claim text.