# Henry Darcys Law Calculator

This darcy calculator is used to find the relationship between the fluid viscosity and the presssure drop over a given distance and Darcy-Weisbach Equation, is used to find the head loss, or pressure loss, due to friction along a given length of pipe to the average velocity of the fluid flow for an incompressible fluid.

Henry Darcy : is a French hydraulic engineer interested in purifying water supplies using sand filters, conducted experiments to determine the flow rate of water through the filters.

Julius Ludwig Weisbach : was a German mathematician and engineer.He also refined the Darcy equation into the still widely used Darcy-Weisbach equation.

## Pressure Drop (Darcy Law) :

This darcy law is basis for all modern analysis of ground water and used to figure out the relationship between the fluid viscosity and the presssure drop over a given distance.Pressure Drop (Darcy Law) is calculated as follows:

Q = -kA (Pb - Pa)μL

Where,

k - Soil coefficient of permeability (m2)

A - Cross section area of flow (m2)

Pa - Final presure (pa)

Pb - Initial Presure (pa)

μ - Viscosity (pa)

L - Length (m)

Q - total discharge in m3/s

Permeability is a property of the porous medium that measures the capacity and ability of the formation to transmit fluids.

## Pressure Loss (Darcy-Weisbach Equation) :

This equauion is used to find the fluid pressure loss due to friction along a given length of pipe to the average velocity of fluid flow for an incompressible fluid.

Δp = fD . LD . pV22

Where,

Δp - Pressure Loss in N/m2

fD - Darcy friction factor

L - Length of the pipe (m)

D - Hydraulic diameter (m)

V - Average velocity of the fluid flow (m/s)

p - Fluid density( kg/m3 )

## Head Loss (Darcy-Weisbach Equation) :

Darcy-Weisbach equation is an empirical equation, which relates the head loss along a given length of pipe to the average velocity of the fluid flow for an incompressible fluid.The below equation is named after Henry Darcy and Julius Weisbach.

hf = fD . LD . V22g

Where,