An equation for a normal depth in a modified horse-shoe shaped tunnel section

摘要

Normal depth is an important parameter occurring in the design of conduits and tunnels carrying water for various purposes like irrigation, power generation and domestic needs under free surface flow conditions. It is equally important in the design of conduits and tunnels conveying waste water under gravity flow situations. As the governing equations for practical conduit shapes are highly complex and implicit in their form, the explicit solution in analytical form becomes tedious and sometimes is not possible. The solution requires tedious methods of trial and error. Tabular and graphical methods that can be made available for solutions involve interpolation and errors of judgment in reading the graphs. Reported herein is an explicit equation for normal depth in a modified horse-shoe shaped conduit/ tunnel section.