Experimental Study On The Effect Of Hydraulic Operation Parameters And Temperature On Water Qulity In Water Distribution Systems

The drinking water quality may have decreased and been the latent menace to human health with the increase of the living standard in China. As a lot of work has been done about the water quality treatment procedures, the study of the water distribution system is coming into our eyes. At present, most of the researchers focus their attention on tubing and the water facilities; the study of the hydraulic regime of water-supply network on the water we drink is little. Based on extensive experimental testing with self-made BAR(Biological Annular Reactor)reactor which can anneal different working conditions, we have found the relationships between the conditions and the water quality. Numerical simulation was made of the inner flow field of the reactor,. By making use of numerical simulation and experiment methods, we studied the effect of different hydraulic parameters and temperature on water quality in water distribution systems.In this paper, by using RNG k ? ?of the FLUENT software, the distribution details of the velocity field had been made. By this means the reliability of the models was validated. The experimental part simulated the operation status of water distribution system by adjusting the rotate speed of the BAR reactor, the inlet flow speed and the water bath temperature. After the experiment period we adopted the methods of artificial sampling analysis, unveiled the different hydraulic parameters and temperature to the mechanisms of the water supply network.Simulation results suggest that it has the same velocity as the flow through the pipe wall. The bigger the velocity is, the less TOC,NH3-N and chloramines are, but when it is bigger than a certain value, the bacteria number is so small that it cannot grow membrane. TOC,NH3-N and chloramines are more and more less with the hydraulic retain time grow longer , the turbidity is higher and the total number of the bacteria is increased. The water turbidity of 48 hours and 72 hours is out of limits. As the temperature is of great importance to the bacteria, and has little effect to the other index, especially when the temperature belongs to 20℃~30℃,which is suitable for bacteria. In order to keep the water safe, the water pipe needs certain velocity and shorter hydraulic retain time, when it comes over 20℃,some management must be done.