초록
Pressure distribution in the water supply system of an apartment complex consisting of 12 buildings and 635 units in total have been investigated numerically. The complex incorporates two zone booster pump system, and around a half of units have pressure reducing valves (PRVs) in them. Calculated hydrostatic pressure without the water flow were compared with their designed and measured counterparts, and they agreed quite well with each other. Then, the pressure and volumetric water flow rate at all units were analyzed, indicating that there are noticeable differences in pressure and flow rate in one unit to another, although the aforementioned minimization technologies of pressure deviation were employed. In order to further reduce the difference in the water flow rate, it is suggested that all the units in the complex have PRVs installed in their water supply system. The effect of setting pressure of the PRVs on the non-uniformity of the flow in each unit and on the reduction of total water supply for the apartment complex have been studied. With the same PRV setting pressure of 3.952 bar (or the gauge pressure of $3.0kg_f/cm^2$), it has been estimated that the suggested system improves the non-uniformity (the coefficient of variation) of the flow rate of apartment complex over the current system, from 8.02% to 6.66%, and reduces the total water supply, from $0.02804m^3/s$ to $0.02766m^3/s$.