Physical Analog of the Linear Reservoir

The linear reservoir is a widely used conceptual model of the rainfall–runoff process. The linear reservoir model transforms rainfall excess to direct surface runoff. The shape of a physical analog of the linear reservoir has been developed mathematically and a laboratory-scale physical model constructed and tested experimentally under steady and unsteady flow conditions. The series of steady flow experiments was conducted to verify the accuracy of a simplifying assumption underlying the development of the physical analog of the linear reservoir. The unsteady series of experiments simulates the rising and recession limbs of the discharge hydrograph from a catchment. Good agreement has been found between the computed and experimental data. The physical analog developed may be useful as a laboratory demonstration apparatus for explaining to hydrology students the concept of the linear reservoir. In addition, in the context of stormwater management in small urban catchments, the linear reservoir physical analog may be a useful flood attenuation device where a linear relationship between surcharge storage and outflow is required.