Thermo-fluid dynamic model of large district heating networks for the analysis of primary energy savings

Among the various heating technologies that can be applied to urban areas district heating is recognized to allow significant reduction in primary energy consumption, provided that the system is properly designed and operated. Thermo-fluid dynamic simulation tools can be of extreme importance in order to achieve this objective. This paper aims at presenting a thermo fluid dynamic model for the detailed simulation of large district heating network and showing how it can be usefully applied to examine options for the reduction of primary energy consumption. The model is tested using experimental data and then applied for analyzing transient operations of the Turin district heating network, which is the largest network in Italy and one of the largest in Europe. A comparison between simulations and experimental results shows that the model is able to predict the temperature in the nodes of the network with good accuracy. The thermal power required to each plant is also calculated with a good level of accuracy. The model can be used for the simulation of operational strategies, thus representing a versatile and important tool for the implementation of advanced management such as the installation of local storage units or the variation of user request schedules.