general

Specific Work

Calculate the specific work of a pump/fan and turbine from primary and secondary pressures and fluid density.

Specific work — sometimes referred to as work per unit charge — is the amount of energy needed to transfer a unit charge between two places in an electric field. It measures the energy that the charge gains or loses while moving, commonly expressed in volts (V) or joules per coulomb (J/C).

Evaluating the energy dynamics and efficiency of electrical systems and components is the main goal of specific work. It offers information on how electrical devices, circuits, and systems operate in terms of voltage requirements, energy consumption, and overall performance.

Applications

Circuit Design
Power Systems
Battery Technology
Electric Motors and Generators
Semiconductor Devices

About This Calculator

Specific work is commonly employed in turbomachines such as fans, pumps, and turbines — representing the amount of work completed per unit weight. By entering the pressure and density values, you can determine the specific work of a fan, pump, or turbine running on an incompressible liquid.

Formulas

$w = \frac{p_1 - p_2}{\rho}$

$t = \frac{p_2 - p_1}{\rho}$

where:

$w$ = Specific Work of Pump (J/kg)
$t$ = Specific Work of Turbine (J/kg)
$p_1$ = Primary Pressure (Pa)
$p_2$ = Secondary Pressure (Pa)
$\rho$ = Density (kg/m³)

Inputs

Primary Pressure(N/m²)

Inlet pressure in newtons per square metre (pascals)

Secondary Pressure(N/m²)

Outlet pressure in newtons per square metre (pascals)

Density(kg/m³)

Fluid density in kg/m³ (source labels unit as kg/m² — that is a source bug)

Results

⚠Density must be greater than zero

Specific Work of Pump or Fan—Nm/kgSpecific work input for a pump or fan in newton-metres per kilogram

Specific Work of Turbine—Nm/kgSpecific work output for a turbine in newton-metres per kilogram