“Computational Civil Engineering - "Intersections" International Journal

284Em. Bârsan, A. Ignat1. INTRODUCTIONIn normal operation conditions, the chlorine dosing established for booster stationsare done after the methodology presented in [1]In case of some failures (breaking of pipe lines) the chlorine distribution isperturbed.The paper has as the a goal the establishing of chlorine concentration modificationsthat are produced when failures (breakings) takes place on pipes and the measuresthat must be taken for the framing of residual chlorine concentration in the limitsrequired by the Law 458/2002 with a minimum total chlorine consumption atinjection booster stations in network.With a personal program are studied the modifications that are produced on anetwork for the cases: network without failures on pipelines and network withfailures on the pipelines and the measures that must be taken in the case of failure.2. ADOPTED MODELChlorine, introduced in distribution network as disinfectant, is transported along apipeline by advection with water average velocity from respective pipeline.Chlorine reaction is of first order (of type C downstream = C upstream exp(-kt)). Atjunctions of two or more pipes , the water mixing is assumed to be complete andinstantaneous. Chlorine concentration that leaves/goes out from junction isweighted average through the flow rates of concentrations that have entered thejunction. For tanks, it is considered that takes place a complete mixing(concentration in tank results from mixing of entered water, of the one from tankand of reactions that take place in tank volume). Chlorine introduction in thedistribution network is done in a number of injection booster stations. Thechoosing of stations for chlorine injections may be done randomly or by imposingof some nodes by modeler. With a number of imposed simulations it is establishedthe minimum chlorine quantity necessary in 24 hours and the stations (nodes) fromwhich is managed so that at the water consuming nodes, the chlorine concentrationto join in the limits specified by Law 458/2002 (0.2 mg/L < c < 0.5 mg/L). On thebase of personal program concerning the hydraulic analysis and the chlorineconcentration establishing at nodes and by means of some dialog windows thenecessary data are introduced and the obtained results are displayed tabular and/orgraphically, that consist in the locations for chlorine injection booster stations, thenecessary chlorine for the injection at each location and chlorine concentrations atnodes for minimum total chlorine consumption in 24 hours. For the study ofinfluences of pipe failures on chlorine consumptions there will be compared thecases: network without and with failures on a pipeline (or pipelines).