The image above represents the Reynold’s number.

To compute for Reynold’s number, four essential parameters are needed and these parameters are **density of fluid (ρ), mean flow velocity (v), diameter of die (d)** and** viscosity (μ).**

The formula for calculating Reynold’s number:

Re = ^{ρvd} / _{μ}

Where:

Re = Reynold’s Number

ρ = Density of Fluid

v = Mean Flow Velocity

d = Diameter of Die

μ = Viscosity

Let’s solve an example;

Given that density of fluid is 14, mean flow velocity is 27, diameter of die is 18 and viscosity is 10. Find the Reynold’s number?

This implies that;

ρ = Density of Fluid = 14

v = Mean Flow Velocity = 27

d = Diameter of Die = 18

μ = Viscosity = 10

Re = ^{ρvd} / _{μ}

Re = ^{(14)(27)(18)} / _{10}

Re = ^{6804} / _{10}

Re = 680.4

Therefore, the **Reynold’s number **is **680.4.**

**Calculating the Density of Fluid when the Reynold’s Number, Mean Flow Velocity, Diameter of Die and Viscosity is Given.**

ρ = ^{Re x μ} / _{vd}

Where:

ρ = Density of Fluid

Re = Reynold’s Number

v = Mean Flow Velocity

d = Diameter of Die

μ = Viscosity

Let’s solve an example;

Given that Reynold’s number is 26, mean flow velocity is 14, diameter of die is 8 and viscosity is 12. Find the density of fluid?

This implies that;

Re = Reynold’s Number = 26

v = Mean Flow Velocity = 14

d = Diameter of Die = 8

μ = Viscosity = 12

ρ = ^{Re x μ} / _{vd}

ρ = ^{26 x 12} / _{(14)(8)}

ρ = ^{312} / _{112}

ρ = 2.78

Therefore, the **density of fluid **is **2.78.**

**Calculating the Mean Flow Velocity when the Reynold’s Number, Density of Fluid, Diameter of Die and Viscosity is Given.**

v = ^{Re x μ} / _{ρd}

Where:

v = Mean Flow Velocity

Re = Reynold’s Number

ρ = Density of Fluid

d = Diameter of Die

μ = Viscosity

Let’s solve an example;

Given that density of fluid is 22, Reynold’s number is 32, diameter of die is 9 and viscosity is 6. Find the mean flow velocity?

This implies that;

Re = Reynold’s Number = 32

ρ = Density of Fluid = 22

d = Diameter of Die = 9

μ = Viscosity = 6

v = ^{Re x μ} / _{ρd}

v = ^{32 x 6} / _{(22)(9)}

v = ^{192} / _{198}

v = 0.96

Therefore, the **mean flow velocity** is **0.96.**

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