# Pressure Source (IL)

Generate specified pressure differential in isothermal liquid network

**Library:**Simscape / Foundation Library / Isothermal Liquid / Sources

## Description

The Pressure Source (IL) block represents an ideal mechanical energy source in an isothermal liquid network. The source can maintain specified pressure differential across its ports regardless of the mass flow rate through the source. There is no flow resistance and no heat exchange with the environment.

Ports **A** and **B** represent the source inlet and
outlet. The input physical signal at port **P** specifies the pressure
differential. Alternatively, you can specify a constant pressure differential as a block
parameter. A positive pressure differential causes the pressure at port **B**
to be greater than the pressure at port **A**.

The block calculates the work performed on the fluid and includes the results in the simulation data log for information purposes:

$${W}_{mech}=\dot{m}\frac{{p}_{B}-{p}_{A}}{\overline{\rho}}$$

$$\overline{\rho}=\frac{{\rho}_{A}+{\rho}_{B}}{2}$$

where:

*W*_{mech}is the mechanical work performed by the source.$$\dot{m}$$ is the mass flow rate generated by the source.

*p*_{A}and*p*_{B}are pressures at ports**A**and**B**, respectively.$$\overline{\rho}$$ is the average fluid mixture density.

*ρ*_{A}and*ρ*_{B}are fluid mixture density values at ports**A**and**B**, respectively. Equations used to compute the fluid mixture density depend on the selected isothermal liquid model. For detailed information, see Isothermal Liquid Modeling Options.

For information on viewing logged simulation data, see Data Logging.

### Assumptions and Limitations

There are no losses due to friction.

There is no heat exchange with the environment.

## Ports

### Input

### Conserving

## Parameters

## Model Examples

## Extended Capabilities

## Version History

**Introduced in R2020a**