Critical Flow

In Chapter 2, we called the depth at which the specific energy was minimum for a given discharge as the critical depth and the corresponding flow as the critical flow. In this chapter, we show that there may be more than one critical depth for a specified discharge in a compound channel. Critical flow has a number of special properties. We discuss these properties and show how they can be used for engineering applications. Then, a procedure for computing the critical depth in a channel is presented. The chapter concludes by discussing the possible number of critical depths in a compound channel and how to determine their values.


Froude Number Downstream Direction Channel Cross Section Bottom Slope Critical Flow 
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