Network Design
Pipe dimensioning, loss calculation, network temperatures and heat density
Network design fixes pipe diameters, temperatures and route layout, and with them the investment costs and heat losses over the network's lifetime. The goal is a hydraulically capable network with low pressure and heat losses at an economic heat line density. This topic area covers pipe dimensioning, pressure-loss and heat-loss calculation, and the choice of network temperatures.
5 articles in this category
District Heating Pipe Sizing: Methods & Criteria
District heating pipe sizing from flow velocity (0.5–2.5 m/s) and pressure gradient (100–200 Pa/m): DN reference values per line type, plus an online calculator.
Pressure Loss Calculation in District Heating
Fundamentals of hydraulic calculation: pipe friction, local resistances and pressure distribution in district heating networks
Heat Loss Calculation According to DIN EN 13941
Calculating heat losses in buried district heating pipes: methods, influencing factors and typical values
Linear Heat Density in District Heating
What is linear heat density and why is it the central metric for the economic viability of district heating networks?
Network Temperatures in District Heating Networks
Supply and return temperatures in district heating networks: calculation, influencing factors and optimisation
Overview: Network Design
Network design answers the central sizing questions of a heat network: which nominal diameters are required on which section, which pressure and heat losses occur, and at which supply and return temperatures the network should operate. The articles in this topic area follow the order in which these questions arise during planning.
The first step is to assess the routes by their linear heat density, which states how much heat is sold per metre of pipe and whether a connection can be justified economically. Pipe sizing then determines the nominal diameters from admissible flow velocities or specific pressure gradients. The pressure loss calculation provides the basis for pump head and pressurization.
The heat loss calculation to DIN EN 13941 quantifies the losses of buried pipes depending on insulation series, laying depth and temperature level. The article on network temperatures links both sides: lower temperatures reduce heat losses but, for the same capacity, require larger mass flows and therefore larger diameters. Network design is consequently iterative and in practice is verified with a network simulation.