Network flow calculation based on the directional nodal potential method for meshed heating networks

Abstract

Heating flow calculation method can determine the temperature and pressure of each node and the mass flow of each branch in the energy network. Since the heating network flow is coupling network flow, it is difficult to deal with discontinuous nodal parameters at the mixing node. The objective of this paper is to obtain characteristics in meshed heating networks based on the physical mechanism analysis and develop a decoupling calculation method for network flow. First, pressure and temperature are proved as two types of physical potentials, for thermal potential energy flow and pressure potential energy flow, respectively. Then, nodal potential energy flow conservation is obtained as the basic rule for the potential energy flow. Due to the transmission speed differences between pressure and thermal potential energy flow, the inflow temperature is different. Using the nodal pressure differences to describe the flow direction of the coupling network flow, temperatures of inflows and outflows at the mixing node are determined. Finally, the directional nodal potential method (DNPM) is developed. The results show that the proposed DNPM can deal with the complex networks containing several potential energy flows with higher convergence speed and more concise modeling formulation.