Flexible district heating network model that predicts mass flow, pressure and temperature losses

Buildings play an important role in urban energy systems. It is no longer enough to simulate building energy use isolated from the supply energy source. Therefore, simulation and optimisation of a district heating networks needs of efficient, fast and realistic models of the individual network elements in order to correctly predict heat losses, temperature propagation, pressure drops and mass flow rates. In addition, the urbanization of new areas beyond the existing ones implies the expansion of the district heating network, demanding the new models to be flexible to adapt to the topology changes. This project presents the mathematical derivation and software implementation in Matlab of a thermo-hydraulic model based in the ‘Element Method’ in which the topology is implemented as an input, and temperature, pressure and mass flow are calculated according to the consumption from the nodes. It is a general tool that could be used as a framework due to its flexibility and adaptability. Currently the presented variables above are calculated for a linear network topology. However, future developments will allow to implement a matrix for more advanced topologies like a tree network. In addition, validation of the temperature loss along the pipes with experimental measurements during steady state conditions have shown a deviation of less than 5%.