Thermo-Hydraulic Finite Element Modelling of District Heating Network by the Uncoupled Approach

Abstract

The modelling of uncoupled fluid flow and heat transfer problems of a district heating network using the finite element method (FEM) is presented. Since the standard thermo-hydraulic pipe elements cannot be directly used for modelling insulation, the main attention was paid to discretisation of multilayered structure of pipes and surrounding by one-dimensional thermal elements. In addition, validity of the finite element method was verified numerically by solving fluid flow and heat transfer problems in district heating pipelines. Verification analysis involves standard single pipe problems and simulation of fragment of district heating in Vilnius. Pressure and temperature results obtained by finite element method are compared with those by other approaches.

A Hybrid State Estimation Approach for Integrated Heat and Electricity Networks Considering Time-scale Characteristics

“…Step 10: estimate the heat power of each consumer Φ L by using (12), the mass flow rate estimated in Step 5, the supply temperature estimated in Step 9 and the specified outlet temperature.…”

“…However, the dynamics of the network were simplified and only the quasisteady energy flow was calculated. In analyzing the dynamics of the DH network, simulation methods were usually used [12]- [15]. The dynamic models of the DH network included transient models [12] and pseudo-transient models [13]- [15].…”

“…In analyzing the dynamics of the DH network, simulation methods were usually used [12]- [15]. The dynamic models of the DH network included transient models [12] and pseudo-transient models [13]- [15]. However, the simulation methods were not practical for real-time monitoring and analysis.…”