DISTRICT HEATING IN THE CITY TRBOVLJE

V delu je predstavljena aplikacija modela CAD HAPN za izračun pretočno-tlačnih razmer v vročevodnem omrežju daljinskega ogrevanja mesta Trbovlje. Aplikacija je v celoti izdelana v objektno usmerjeni programski tehnologiji, razviti na Fakulteti za strojništvo Univerze v Mariboru. Osnova so numerični moduli HAPN/HW (hidravlična analiza cevne mreže/vroča voda), ki omogočajo: — določanje smeri pretoka v posameznih odsekih cevne mreže— izračun volumskega pretoka v posameznih odsekih cevne mreže— izračun padca tlaka v posameznih odsekih cevne mreže— izračun tlaka v vozliščih— pretočno-tlačno analizo cevne mreže s poljubnim številom vtokov in iztokov— pretočno-tlačno analizo cevne mreže s črpalnimi postajami— pretočno-tlačno analizo cevne mreže pri spremenljivo odprtih ventilih— pretočno-tlačno analizo drevesno, zankasto ali kombinirano oblikovane cevne mreže. Podatki o cevni mreži, porabnikih, o topologijah itn. so pridobljeni pri Javnem podjetju Komunala Trbovlje d.o.o. in navedeni v tabelarični obliki. Vsi izračuni so izvedeni za faktorja istočasnosti 0,5 in 1,0. Na osnovi izsledkov so analizirane možnosti zmanjšanja obratovalnega tlaka in letnih črpalnih stroškov. Navedene so tudi enačbe za izračun toplotnih izgub skozi izolirane cevovode, ki potekajo v zraku oziroma kinetah.This work present the CAD application HAPN design to calculate flow – pressure conditions in hot water transmission systems. The application is completely designed in object – oriented programming technology, which was developed on the Faculty of mechanical engineering, University of Maribor. Its basis are numerical modules HAPN/HW (hydraulic analysis of pipe networks/hot water), which enable: – determination of flow direction in pipe network section– calculation of volume flow in pipe network sections– calculation of pressure drops in pipe network sections– calculation of pressure in nodes– flow-pressure analyses of pipe network with any number of inflows and outflows– flow-pressure analyses of pipe network with pumping stations– flow-pressure analyses of conditions by part opened valves– flow-pressure analyses of pipe networks with tree-like, loop and combined shape. The data on pipe network, consumers, topology, etc. are from Javno podjetje Komunala Trbovlje d.o.o. and are entered in tabular form. All calculations are made for the simultaneity factor 0,5 and 1,0. From the results the potential to reduce pressure drop and the annual pumping costs are analyzed. Also the equations for the calculation of heat losses through the insulated pipes held in the air or in canals are given