Mathematical modeling and computer aided planning of communal sewage networks

In the paper the basic questions connected with modeling of wastewater networks are presented. Methods of modeling basic sewage parameters and appropriate calculation algorithms are described. The problem concerns the gravitational networks divided by nodes into branches and sectors. The nodes are the points of connection of several network segments or branches or the points of changing network parameters as well as of location of sewage inflows to the network. The presented algorithms for networks hydraulic calculation concern sanitary or combined sewage nets. It is assumed that the segments parameters such as shape, canal dimension, bottom slope or roughness are constant. Because of these assumptions all relations considered concern the steady state conditions for the network. The calculation of flow velocities and the filling heights in the segments of the wastewater net are carried out for the known slopes and diameters of the canals.