Modification of Hunter%26apos;s Curve in the Perspective of Water Conservation

作者：Mazumdar Asis^*; Jaman Hasanur; Das Subhasish

来源：Journal of Pipeline Systems Engineering and Practice, 2014, 5(1): 04013007.

DOI：10.1061/(ASCE)PS.1949-1204.0000150

• Plumbing system
• Water conservation
• Hunter%26apos
• s curve
• Water demand load
• Binomial probability distribution
• Confidence level

Plumbing-system designers, who routinely use Hunter%26apos;s curve for estimating domestic demand, actually solve complex problems based on the probabilistic approach. Recently, serious questions have arisen about the accuracy of Hunter%26apos;s curve. In some instances, using the curve to estimate the water-demand load has given highly inflated results. However, this consistent problem in applying the curve to design should in no way be interpreted as a criticism indicating that Hunter%26apos;s basic research and approach are incorrect. Many things have changed since 1940 when Roy B. Hunter%26apos;s BMS65 Methods of Estimating Loads in Plumbing Systems, was published as a national standard in the United States. In the context of water conservation, which should be the primary goal in the global water-stressed scenario, designers are giving importance to using low-water-use (demand) fixtures. Merely recommending the use of low-water-flow fixture cannot address the issue of water conservation. Hunter%26apos;s curve was based on 1940 high-flow fixtures with a very high confidence level (CL) of 99%. Hunter%26apos;s curve needs to be modified in this context. In the present study, to obtain the optimal water demand of the plumbing system, Hunter%26apos;s curve has been modified by incorporating low flow rates of modern fixtures, the reduced probability of a modern fixture being on at any moment, and reduced CL in the binomial probability function as used by Hunter. Low-flow fixtures will be meaningful when the demand calculations must also address the issue of water conservation, and in this context, this paper%26apos;s modified Hunter%26apos;s curve will address optimal design of plumbing systems thereby facilitating the conservative and sustainable use of water.

• 出版日期2014-2