Hydraulic Calculation of Copper Pipelines for Heating and Internal Gas Supply Systems

Copper pipelines are widely used while designing modern heating systems, water and gas supply of residential buildings and these pipelines have a number of advantages in comparison with steel and plastic pipelines. The main reason for limited use of copper pipes is their cost which is practically twice as much as cost of steel pipes, and four times higher than the coat of polypropylene pipes. Modern design standards in Belarus do not contain specific requirements for calculation of copper pipelines. Therefore hydraulic calculation of heating systems has been considered and analyzed on the basis of norms of Russian Federation. The drawback of all theoretical calculations presented in Russian standards is their abstraction from general laws of fluid and gas mechanics. For this reason theoretical foundations of hydraulic calculations for all pipelines have been considered and expressions have been given for determination of pressure loss due to friction and in local loss. Main flow regimes have been considered on the basis of I. Nikuradze’s experiments in order to determine linear losses and dependences for determination of friction coefficient in laminar, transient and turbulent modes have been presented in the paper. Values of local loss coefficient for main pipeline elements are given for calculation of pressure loss and the paper also shows determination of value z with due account of equipment capacity. An analysis of nomograms presented in Russian norms and researches has been carried out; shortcomings have been revealed and the ways directed on their perfection have been found. Nomograms for calculation of specific pressure losses in heating systems and internal gas supply have been constructed on the basis of natural gas and propane with due account of dependences presented in the paper. Nomograms for finding equivalent length of a single local loss have been constructed for calculation of internal gas supply systems.