Dynamic Temperature Simulation in District Heating Systems in Denmark Regarding Pronounced Transient Behaviour / Danijos Šilumos Tiekimo Sistemų Modeliavimas, Įvertinant Nestacionarų Temperatūros Pasiskirstymą Tinkle

Abstract

Abstract.A dynamic performance of district heating systems was analysed with an emphasis on temperature profile distortion throughout a heating system network. Therefore, a modelling approach (the so-called node method) developed at the Technical University of Denmark was applied. For comparison purposes, commercial TERMIS software was also used in this work. Typical supply conditions were investigated in the considered district heating systems in Denmark. Large and sudden temperature changes in supply temperature were depicted in the district heating system in Madumvej while the pronounced transient supply conditions of temperature wave were exhibited in the district heating system in Naestved. Time-dependent consumer data from the district heating systems were applied to compare the results obtained from modelling approaches. Based on the analysis of temperature wave propagation through the network, it was noted that temperature wave spread unevenly on different locations of the network.

Heat transmission over long pipes: New model for fast and accurate district heating simulations

“…On the other hand, Gabrielaitiene has provided major contributions through several studies comparing the node method with other modelling approaches [20], using the commercial software TERMIS [21][22][23] and DH monitoring data [24]. The main outcomes of these comparisons are significant discrepancies between the simulated temperatures and the monitored ones at distant points of the networks that are reached after passing through several bends and connections.…”

Stochastic Coordinated Management of Electrical–Gas–Thermal Networks in Flexible Energy Hubs Considering Day-Ahead Energy and Ancillary Markets

“…The proposed scheme in this section is presented based on the multi-energy system in Figure 1, which has an IEEE 33-bus electrical distribution network [59], Madumvej 15-node thermal network [60], and a 4-node gas network [6]. The base power for electrical, thermal, and gas networks is 1 MVA, 1 MW, and 1 MW, respectively.…”

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