Critical appraisal of various techniques used for flow modeling in non- prismaticcompound open channel flow

Each river in the world is unique. Some are gently curve, others meander, and some others are relatively straight and skewed. The size of river geometry also changes from section to section longitudinally due to different hydraulic and surface conditions called non -prismatic channel. Much works done on river hydraulics are found to bed non prismatic compound channels. There has also been significant progress of work in meandering channels. But an area which has been somewhat neglected is that of non-prismatic channels. This paper scrutinizes various phenomenon related to non-prismatic channel in different type of flow systems. As discharge prediction is a vital issue in flood risk management and more important for a river in changed geometry. Therefore, a critical appraisal of the various techniques developed by various researchers across the globe for the past few decades to predict the stage-discharge relationship of a non-prismatic compound channels is extremely essential. Because it will facilitate the researchers to focus on the area of river hydraulics and that may lead to solve for other related objectives. Many methods adopted and developed by earlier researchers for both prismatic and non-prismatic compound channel areanalysed in this paper.