turbulent boundary layer

Standing from the point of mathematics and th rough determining the parameters(dis-count rate)for boundary flow formula of the water supply pipeline net,authors deduces a new for-mula which is connect ed with the level of social and economic development.

将货币的时间价值引入界限流量公式,从而建立一个与社会经济发展水平相关的动态界限流量公式,并以实例计算对比差异,阐述动态界限流量公式对当前给水管网设计、管网造价的意义。