.TransiEnt.Storage.Gas.GasStorage_varXi_L2

Information

1. Purpose of model

This model represents a compressed gas storage for real gases with variable composition. It extends Base.PartialGasStorage_L2.

2. Level of detail, physical effects considered, and physical insight

The model consists of a volume, in which the gas located. Pressure losses inside the volume and during charging and discharging are neglected. There is no discretisation of the flow field or the heat transfer. The heat transfer is modelled using a replacable heat transfer model, the default model uses a constant heat transfer coefficient. The parameter variableCompositionEntries can be used in case that not all components are freely variable, e.g. when hydrogen is fed into natural gas. This reduces the number of states.

3. Limits of validity

The model is only valid for negligible pressure losses and negligible changes of the heat transfer coefficient (other heat transfer models can be used). For high pressures there are errors due to errors in the gas models. The gas in the storage is always ideally mixed, there is only one composition in the storage.

4. Interfaces

gasPortIn and gasPortOut: Real gas input and output

heat: heat port for the heat flow into/out of the storage

p_storage: signal output of the gas pressure

5. Nomenclature

(no elements)

6. Governing Equations

Simple mass and energy balances are used. For the compositions, component mass balances are added.

7. Remarks for Usage

(no remarks)

8. Validation

This model is not validated and might produce different results depending on the energy balance equation used in the base model.

9. References

(no remarks)

10. Version History

Model created by Carsten Bode (c.bode@tuhh.de) in Apr 2017

Modeli modified by Carsten Bode (c.bode@tuhh.de) in Apr 2021 (added simplifications for composition)