Laboratory Investigation of Non-Darcy Flow through Rounded Porous Materials

Document Type : Research Article


1 Civil Engineering, Faculty of Engineering, Yasouj University; Yasouj, Iran

2 Soil Science, Agricultural College, Yasouj University; Yasouj, Iran.


Application of aggregate coarse rockfill in hydraulic structures is increasing due to their special ‎properties and is imperative due to its importance and their specific characteristics. Accurate ‎investigation of the flow properties through coarse materials in order to determine hydraulic ‎parameters is one of the most important necessities considering high application such media in civil ‎works. On the other hands, there is less works about transitional flow through coarse materials. In ‎order to study the flow behavior through granular materials a packed column test was built. Some ‎experiments have done on three samples of rounded particles with average size of 10.348mm, ‎‎12.127mm and 17.785mm and seepage flow and upstream and downstream heads were recorded in ‎a certain intervals. By using some calculating and depicting some graphs, their behaviors have ‎evaluated. Using the relationship of flow velocity- hydraulic gradient, it was fund that such ‎relationship is non-linear and this is a strong criteria confirming non-Darcy flow. The evaluating of ‎results of this study by statistical indexes and its comparison by Ergun (1952), Kovacs (1981) and ‎Sidiropoulou et al (2007) relationships showed that the relation of Sidiropoulou et al (2007) is more ‎accurate than the other equations. The result of Reynolds number-friction factor curves has shown ‎that with increasing the grain size diameter, friction factor is decreased and Reynolds number is ‎increased.‎


Main Subjects

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