Mathematical Modelling of Heating System Hydraulic Modes

This paper presents a numerical model which allows one to simulate fluid flow in a complex, arbitrarily configured multichannel system with a capability of automatic visualization of its structure. The system is composed of its primary elements, channels, which are joined together with a predefined set of connecting elements (local hydraulic resistances, junctions). The fluid flow in the model is governed by the mass, momentum and energy conservation equations in their incompressible form. System structure mapping is achieved with a special algorithm which forms matrices of internal and external boundary conditions. Matrix formation is based on the connecting elements generalized linearized models. Based on the model, an application has been developed, which allows one to calculate a steady-state solution for the fluid flow problem in a multichannel system of the arbitrary structure. The application has been implemented for heat networks' hydraulic regime modeling. A heating network is represented as a system of channels connected together in a certain manner and depending on the heat supply scheme. The results obtained on the model allow quick investigation of the heat network operation parameters and demonstrating them visually in an informative way, both at the design stage and at operation maintenance. The model also allows for simulation of complete or partial channel blockage, consumer flow rate change and emergency situations.