期刊文献+
共找到1篇文章
< 1 >
每页显示 20 50 100
Power Law Exponents for Vertical Velocity Distributions in Natural Rivers
1
作者 Hae-Eun Lee Chanjoo Lee +2 位作者 youg-jeon kim Ji-Sung kim Won kim 《Engineering(科研)》 2013年第12期933-942,共10页
While log law is an equation theoretically derived for near-bed region, in most cases, power law has been researched by experimental methods. Thus, many consider it as an empirical equation and fixed power law exponen... While log law is an equation theoretically derived for near-bed region, in most cases, power law has been researched by experimental methods. Thus, many consider it as an empirical equation and fixed power law exponents such as 1/6 and 1/7 are generally applied. However, exponent of power law is an index representing bed resistance related with relative roughness and furthermore influences the shapes of vertical velocity distribution. The purpose of this study is to investigate characteristics of vertical velocity distribution of the natural rivers by testing and optimizing previous methods used for determination of power law exponent with vertical velocity distribution data collected with ADCPs during the years of 2005 to 2009 from rivers in South Korea. Roughness coefficient has been calculated from the equation of Limerinos. And using theoretical and empirical formulae, and representing relationships between bed resistance and power law exponent, it has been evaluated whether the exponents suggested by these equations appropriately reproduce vertical velocity distribution of actual rivers. As a result, it has been confirmed that there is an increasing trend of power law exponent as bed resistance increases. Therefore, in order to correctly predict vertical velocity distribution in the natural rivers, it is necessary to use an exponent that reflects flow conditions at the field. 展开更多
关键词 Vertical VELOCITY Distribution Power LAW EXPONENT Natural RIVERS Field Measurement Flow Resistance
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部