It is also of significant interest in such diverse fields as Civil and Chemical Engineering, and Biology and Medicine. Early work in the subject was essentially empirical and despite many advances in mathematical analysis the complexity of the flow of real fluids is such that very few complete solutions of flow situations exist and therefore a large part of the topic of fluid flow in closed conduits remains an empirical science. In this area, three sets of experiments are considered which are all concerned with the flow of water through circular pipes or tubes, the head loss through pipe fittings, the loss of head at changes in pipe section, the head loss which occurs at entry and exit to pipes, the pressure loss across valves and valve characteristics. The flow of fluids in closed conduits or pipes is a major topic in the Mechanical Engineering subject of Mechanics of Fluids due to its practical importance in so many fields of study.
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