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• Trial Software

# Constant Volume Chamber (TL)

Physical enclosure with fixed liquid volume

## Library

Thermal Liquid/Elements

## Description

The Constant Volume Chamber (TL) block represents a physical enclosure with a fixed volume of liquid. The enclosure can exchange mass and energy with its surroundings, allowing its internal pressure and temperature to evolve over time. Heat transfer occurs via convection, as liquid enters or exits the chamber, and conduction, as thermal energy flows through the chamber walls and the liquid itself.

Port A is a thermal liquid conserving port that corresponds to the chamber inlet. Pressure in the chamber equals the pressure at this port. Port Q is a thermal conserving port associated with the heat flux through the chamber wall. Temperature in the chamber equals the temperature at this port.

The following equations govern the dynamic evolution of liquid pressure and temperature in the chamber:

where

 V Chamber volume pint Chamber pressure Tint Chamber temperature Mass flow rate into chamber βint Liquid isothermal bulk modulus αint Liquid isobaric thermal expansion coefficient cint Liquid specific heat uint Liquid specific internal energy ρint Liquid mass density φA Thermal energy flux into chamber through port A Thermal energy flux into chamber through port Q

## Assumptions and Limitations

• Chamber walls are perfectly rigid.

## Dialog Box and Parameters

Chamber volume

Enter the volume of liquid present in the chamber. This volume remains constant throughout the simulation. Values must equal or exceed zero. The default value is 1e-3 m^3.

Characteristic length

Enter the characteristic length of the chamber. This length is the average distance that liquid must traverse as it leaves the chamber. The default value is 1e-1 m.

Fluid initial pressure

Enter the absolute pressure of the enclosed liquid at time zero. The default value is 1 atm.

Fluid initial temperature

Enter the temperature of the enclosed liquid at time zero. The default value is 293.15 K.

## Ports

The block has one thermal liquid conserving port, A, and one thermal conserving port, Q.