Analysis of a Long Wave of Depression from the Point of View of Energy Motion

Abstract

The paper considers the problem of unsteady water flow in the form of a long wave with a decrease in the water level. The flow is generated by a moving wave-maker in a horizontal, infinitely long channel. Under the action of constant external force, the flow tends to a steady and uniform movement, which parameters are of particular interest. It derives equations to calculate mean velocity, depth, and water discharge, utilizing the principles from the theory of energy motion. Also, it identifies the conditions under which maximum water discharge or flow power occurs. The case of uniform flow of fluids in a horizontal channel revealed a principal contradiction between the theory of energy motion and the theory of uniform flow.