Fluid Mechanics

Abstract

AbstractThis article provides an overview of the fundamentals and common applications of fluid mechanics in engineering settings, especially in the context of chemical and process engineering. Starting with the definition of a fluid, types of fluids, concept of continuum, and the Eulerian and Lagrangian viewpoints are introduced. This sets the stage for the development of the Reynolds transport theorem required to apply the laws of physics (conservation of mass and energy and Newton's laws of motion) to open systems in moving fluids. Integral and differential forms of these laws as applied to the moving fluids are obtained. Selected applications such as the estimation of frictional pressure drop in pipes and in packed columns are presented in detail. Similarly, the external flow of fluids over variously shaped objects such as sphere, cylinder, and circular discs is discussed next. The effects of solid boundaries on the detailed flow kinematics such as separation of shear layers and various flow regimes which directly influence the macroscopic flow are discussed briefly. The preceding treatment limited thus far to simple Newtonian fluids is then extended to more complex fluids such as non‐Newtonian and/or the flow of multiphase systems (gas–liquid, liquid–liquid, and gas–solid) in pipes, which are discussed in brief. The commonly used experimental tools in fluid mechanics for velocity, flow, temperature, and pressure measurements in single and multiphase flows are also introduced briefly, followed by the measurement of average holdup in multiphase flow situations. A short discussion of the other important areas of fluid mechanics not covered here is offered, supported by an extensive bibliography for further reading.