TRNSYS Type 840: Simulation model for PCM/water storage tanks (Version 2.0)

The simulation model Type 840 was developed at the Institute of Thermal Engineering, Graz University of Technology, within the framework of the European Project PAMELA (2004), the IEA SHC TASK 32 and a national research project (2006). The model enables a detailed simulation of water tanks with integrated PCM modules of different geometries (cylinders, spheres and plates) or tanks filled with a PCM slurry. An update was made by Christoph Moser in the European project Hybrid-BioVGE (2022). 

The heat transfer in the PCM modules is calculated assuming conduction only, convection effects in the liquid phase are neglected. The transient heat conduction in the PCM modules is modelled with a two-dimensional (cylinders, plates) or one-dimensional (spheres) finite differences approach. The phase change process is modelled with the enthalpy method, assuming the specific enthalpy as a continuous function of temperature. The model also takes into account the supercooling and hysteresis that occur with many PCMs. The model is available in a TRNSYS 17 and a TRNSYS 18 version.