Analysis On Design Flow Of Water Supply In Residential Area

As the rise, development and prosperity of real estate industry, more and more residential areas appeared. As the necessary matching facility, pipe network of water supply in residential area, has been attached more importance to, and the determination on design flow of water supply has been a critical problem of designers. Design flow calculation of water supply in residential area is the basement of pipe network hydraulic computation, is the criterion of determination on pipe diameter, head loss and system pressure. Design flow has a bearing on the most unfavorable condition choosing, pressure guarantee and pump investment. Only appropriate design flow can make sure the normal operation of whole water supply system.Aimed to design flow of water supply in residential area, firstly, the research explained the essential features and water supply situation of residential area. Then the research analyzed the designing of water supply flow, and derived the formula of design flow in residential area. At last, quoted a engineering example, proved the practicability of the formula.The residential area is composed of several independent constructions, and its characteristic of water supply is different from the municipal water supply system and indoor water supply system. Design flow of water supply in residential area between design flow of municipal system and indoor system. So far, there wasn’t a unified formula for residential area. If following the municipal system, the design flow would be choose too small, instead, following the indoor system, the design flow would be choose too large. It is so difficult to derive the formula from actual calculation, so, designers choose the higher one from municipal system and indoor system. But that’s very complicated and unsatisfying.Choosing the common residence as model, we calculated the flow by design flow probability calculation and maximum average flow calculation, and analyzed the result. Proposed using of two calculating results of intersection "O", critical flow N’G, as the decision point. When it is lower than N’G, it should use curve fitting to derive the formula. The research also obtained the figure of average flow probability Uo and total equivalent number NG, which make the result more simple and clear.Design flow of water supply in residential area between maximum hour design flow and average hour design flow. According to different kinds of residences, derived design flow formula respectively. When the fixture unit number is lower than N’G, the formula should be used, when exceeds N’G, the maximum hour design flow formula should be used. The critical equivalent is related to the population number, hourly variation coefficient and life water quota. Each of them changed, the critical equivalent will be changed. Using the critical equivalent figure could make choosing formula easy.