Optimization method for hydraulic calculation of large-scale cooling and heating network

Proposes an optimization method for hydraulic calculation of large-scale cooling and heating network. Aiming at the minimum annual equivalent cost of the pipe network, establishes the single-variable nonlinear relationship between annual equivalent cost and pipe diameter. Obtains the economic pipe diameters of different pipe network sections based on differential method. Take a project as the example for analysis, adopts two different methods for calculation, including the velocity assumption method and the optimum method proposed in this paper. The results show that the energy saving and the economy of the optimization design method are superior to the traditional design method. The running energy consumption of water pumps is reduced by 39.5%, and the cooling/ heating loss is decreased by 11.2%. For annual equivalent cost, a saving of 10.1% is obtainable, with significant economic benefit.