## How to Calculate and Solve for Relative Apparent Viscosity (for Concentrated suspension) | Rheology

The image above represents relative apparent viscosity (for concentrated suspension).

To compute for relative apparent viscosity (for concentrated suspension), three essential parameters are needed and these parameters are Intrinsic Viscosity (ηi), Solid Landing (φ) and Maximum Solid Landing (φm).

The formula for calculating relative apparent viscosity (for concentrated suspension):

ηra = (1 – φ / φm)-(ηim

Where:

ηra = Relative Apparent Viscosity
ηi = Intrinsic Viscosity
φ = Solid Landing
φm = Maximum Solid Landing

Let’s solve an example;
Find the relative apparent viscosity when the intrinsic viscosity is 20, the solid landing is 32 and the maximum solid landing is 12.

This implies that;

ηi = Intrinsic Viscosity = 20
φ = Solid Landing = 32
φm = Maximum Solid Landing = 12

ηra = (1 – φ / φm)-(ηim
ηra = (1 – 32 / 12)-(20) x 12
ηra = (1 – 2.66)-240
ηra = (-1.66)-240
ηra = 5.705e-54

Therefore, the relative apparent viscosity (for concentrated suspension) is 5.705e-54.

## How to Calculate and Solve for Relative Apparent Viscosity | Rheology

The image above represents relative apparent viscosity.

To compute for relative apparent viscosity, two essential parameters are needed and these parameters are Viscosity of Non-Newtonian Fluid (ηa) and Viscosity of Continuous Phase (ηc).

The formula for calculating relative apparent viscosity:

ηra = ηa / ηc

Where:

ηra = Relative Apparent Viscosity
ηa = Viscosity of Non-Newtonian Fluid
ηc = Viscosity of Continuous Phase

Let’s solve an example;
Find the relative apparent viscosity when the viscosity of non-newtonian fluids is 44 and the viscosity of continuous phase is 11.

This implies that;

ηa = Viscosity of Non-Newtonian Fluid = 44
ηc = Viscosity of Continuous Phase = 11

ηra = ηa / ηc
ηra = 44 / 11
ηra = 4

Therefore, the relative apparent viscosity is 4.

Calculating for Viscosity of Non-Newtonian Fluids when the Relative Apparent Viscosity and the Viscosity of Continuous Phase is Given.

ηa = ηra x ηc

Where;

ηa = Viscosity of Non-Newtonian Fluid
ηra = Relative Apparent Viscosity
ηc = Viscosity of Continuous Phase

Let’s solve an example;
Find the viscosity of non-newtonian fluid when the relative apparent viscosity is 16 and the viscosity of continuous phase is 8.

This implies that;

ηra = Relative Apparent Viscosity = 16
ηc = Viscosity of Continuous Phase = 8

ηa = ηra x ηc
ηa = 16 x 8
ηa = 128

Therefore, the viscosity of non-newtonian fluid is 128.