Reservoir (TL)

Thermal liquid reservoir at constant temperature and pressure


Thermal Liquid/Elements


The Reservoir (TL) block represents an infinite reservoir at fixed pressure and temperature. The reservoir and its inlet can be at atmospheric pressure or at a specified pressure. Port A, a thermal liquid conserving port, represents the reservoir inlet.

The inlet temperature depends on the direction of liquid flow. If liquid flows into the reservoir, the inlet temperature equals that of the upstream liquid. The reservoir acts as a heat sink. If liquid flows out of the reservoir, the inlet temperature equals that of the reservoir. The reservoir acts as a heat source.

To ensure a smooth temperature change at the reservoir inlet during liquid flow reversal, the block includes heat conduction along a length equal to the effective diameter of the pipe. This diameter is a function of the specified cross-sectional area of the inlet pipe.

This block also functions as a reference point for pressure and temperature measurements in a pipe network. These measurements are relative to reservoir pressure and temperature, respectively.

Assumptions and Limitations

  • Reservoir temperature is constant.


Reservoir pressure specification

Select whether to model the reservoir at atmospheric pressure or at a specified pressure. The default setting is Atmospheric pressure.

Reservoir pressure

Enter the desired pressure in the reservoir. This pressure remains constant during simulation. The default value is 1.01325 bar.

Reservoir temperature

Enter the desired temperature in the reservoir. The default value is 293.15 K.

Cross-sectional area at port A

Enter the cross-sectional area of the reservoir inlet pipe. The block uses this area to determine the characteristic length of the pipe along which heat conduction occurs. The default value is 1e-2 m^2.


The block has one thermal liquid conserving port, A.

Introduced in R2015a

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