THERMAL ENERGY STORAGE - Title

Thermal Energy Storage Component Model

THERMAL ENERGY STORAGE - model overview

Model Overview

Author / organization: Benedikt Leitner / AIT

Domain: Thermal storage

Intended application: Return-supply connections in, e.g., district heating networks and possibly in combination with a heater unit

Modelling of spatial aspects: Discretized (single device)

Model dynamics: Dynamic

Model of computation: Time-continuous

Functional representation: Explicit

THERMAL ENERGY STORAGE - input and output

Input and Output

Input variables : Modelica.Fluid.Interfaces.FluidPort port_a (acausal): fluid port at return side

Output variables :

  • Real T_i: temperature of layer I [K]
  • Modelica.Fluid.Interfaces.FluidPort port_b (acausal): fluid port at supply side

THERMAL ENERGY STORAGE- related documents

THERMAL ENERGY STORAGE- description

Short Description

A model of a stratified storage tank for thermal energy storage. Intended to be used for return-supply connections in, e.g., district heating networks and possibly in combination with a heater unit. The temporal resolution is minutes to hours. The model represents a stratified storage tank. The tank uses several volumes to model the stratification. The tank has a fixed volume. Thus, the same mass flow injected at the top of the tank leaves the tank at the bottom and vice versa. Heat conduction is modelled between the volumes through the fluid, and between the volumes and the ambient. Effects modelled include buoyancy, heat transfer between layers as a result of heat conduction and mass flow as well as heat transfer of each layer to the ambient. The model is able to capture flow reversals and zero flow.

Present use / development status

The model is part of AIT’s internal Modelica library for district heating and is usable for co-simulation with electric network models. The Modelica library uses the Modelica standard library and the IBPSA library as a core.

THERMAL ENERGY STORAGE

Model Details