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Reynolds Number Calculator
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Reynolds number Calculator is used to calculate any of the quantity related to fluid flow like Reynolds number, density, critical velocity, Coefficient of viscosity and diameter if some of these quantities are known.

The Reynolds Number is given by

R = $\frac{\rho V D}{\mu}$

Where $\rho$ = Density,
V = Critical  Velocity,
D = Diameter,
$\mu$ = Viscosity,
R = Reynolds number.

The Reynolds Calculator works only for the incompressible fluid flow.

## Steps for Reynolds Number Calculator

Step 1 :

Analyze the given quantites in the problem.

Step 2 :

Using the Reynolds number formula, we get
R = $\frac{\rho V D}{\mu}$
where $\rho$ = Density,
V = Velocity,
D = Diameter,
$\mu$ = Viscosity,
R = Reynolds number.

Substituting the given values in the above formula, we get the desired unknown quantity

## Problems on Reynolds Number Calculator

1. ### A fluid of viscosity of 0.4 Ns/m2 and relative density of 900 kg/m3 flows through a 20 mm diameter pipe with a velocity of 2.5 m/s. Find the Reynolds number?

Step 1 :

Analyze the given quantites in the problem

Reynolds number R = ?

Density $\rho$ = 900 kg/m3,

Velocity V =2.5 m/s,

D = Diameter = 20 mm,

$\mu$ = 0.4 Ns/m2

Step 2 :

Using the Reynolds number formula, we get
R = $\frac{\rho V D}{\mu}$
where $\rho$ = Density,
V = Velocity,
D = Diameter,
$\mu$ = Viscosity,
R = Reynolds number.

Substituting the given values in the above formula, we get the desired unknown quantity

R = $\frac{900 \times 2.5 \times 20 \times 10^{-3}}{0.4}$

Reynolds number R = 112.5

2. ### A crude oil of reynolds number 400 having viscosity 0.9 N-s/m2 and relative density 500 kg/m3 is flowing through the circular pipe of diameter 100 mm.Calculate the velocity of the fluid?

Step 1 :

R=400,

$\mu$ = 0.9,

$\rho$ = 500 kg/m3,

D = 100 mm

V =?

Step 2 :

Using formula

R = $\frac{\rho V D}{\mu}$

V = $\frac{R \mu}{\rho D}$

= $\frac{400 \times 0.9}{500 \times 0.1}$