Numerical Prediction of Temperature Waves in Complex Pipeline Networks

Abstract

A numerical prediction of temperature waves in complex pipeline networks, such as in district heating systems, is important for adjustment of the loads of heat power plants and pump stations with dynamic consumption needs during changes of the outside air temperature, the wind intensity, the solar radiation, or system startups and shut-downs. A thermal-hydraulic model and computer code are developed for simulation of the thermal transients in district heating systems. They are based on the high-order accurate numerical solution of the transient energy equation, and the hydraulic prediction of pressure and fluid flow rates within the complex pipe network. Numerical prediction of temperature waves, caused by an increase and decrease of the heat power plant load, are simulated for real operating conditions of the district heating system. The obtained temperature front propagations are in good agreement with data measured at three consumer substations located in different parts of the district heating network and at different distances from the heat plant.