Engineering Fluid Mechanics
Engineering fluid mechanics is the study of how fluids behave and interact with their surroundings in engineering applications. It involves the principles of fluid statics, fluid dynamics, and the application of these principles to solve engineering problems related to fluid flow, pressure, and forces. This field is essential for designing and analyzing systems involving liquids and gases, such as pipelines, pumps, and hydraulic systems.
5 Key excerpts on "Engineering Fluid Mechanics"
eBook - ePub- Richard Gentle, Peter Edwards, William Bolton(Authors)
- 2001(Publication Date)
- Newnes(Publisher)
...3 Fluid mechanics Summary Fluid mechanics is the study of the behaviour of liquids and gases, and particularly the forces that they produce. Many scientific disciplines have an interest in fluid mechanics. For example, meteorologists try to predict the motion of the fluid atmosphere swirling around the planet so that they can forecast the weather. Physicists study the flow of extremely high temperature gases through magnetic fields in a search for an acceptable method of harnessing the energy of nuclear fusion reactions. Engineers are interested in fluid mechanics because of the forces that are produced by fluids and which can be used for practical purposes. Some of the well-known examples are jet propulsion, aerofoil design, wind turbines and hydraulic brakes, but there are also applications which receive less attention such as the design of mechanical heart valves. The purpose of this chapter is to teach you the fundamentals of Engineering Fluid Mechanics in a very general manner so that you can understand the way that forces are produced and transmitted by fluids that are, first, essentially at rest and, second, in motion. This will allow you to apply the physical principles behind some of the most common applications of fluid mechanics in engineering...
eBook - ePub- William S. Janna(Author)
- 2020(Publication Date)
- CRC Press(Publisher)
...1 Fundamental Concepts Fluid mechanics is the branch of engineering that deals with the study of fluids—both liquids and gases. Such a study is important because of the prevalence of fluids and our dependence on them. The air we breathe, the liquids we drink, the water transported through pipes, and the blood in our veins are examples of common fluids. Further, fluids in motion are potential sources of energy that can be converted into useful work—for example, by a waterwheel or a windmill. Clearly, fluids are important, and a study of them is essential to the engineer. After completing this chapter, you should be able to: Describe commonly used unit systems; Define a fluid; Discuss common properties of fluids; Establish features that distinguish liquids from gases; and Present the concept of a continuum. 1.1 DIMENSIONS AND UNITS Before we begin the exciting study of fluid mechanics, it is prudent to discuss dimensions and units. In this text, we use two unit systems: the British gravitational system and the international system (SI). Whatever the unit system, dimensions can be considered as either fundamental or derived. In the British system, the fundamental dimensions are length, time, and force. The units for each dimension are given in the following table: British Gravitational System Dimension Abbreviation Unit Length L foot (ft) Time T second (s) Force F pound-force (lbf) Mass is a derived dimension with units of slug and defined in terms of the primary dimensions as 1 slug = 1 1 bf ⋅ s 2 ft (1.1) Converting from the unit of mass to the unit of force is readily accomplished because the slug is defined in terms of the lbf (pound-force). Example 1.1 An individual weighs 150 lbf. a. What is the person’s mass at a location where the acceleration due to gravity is 32.2 ft/s 2 ? b. On the moon, the acceleration due to gravity is one-sixth of that on earth. What is the weight of this person on the moon? Solution a...
eBook - ePub- James Patrick Abulencia, Louis Theodore(Authors)
- 2011(Publication Date)
- Wiley-AIChE(Publisher)
...Key terms in these two topics that are of special interest to engineers are covered in this chapter. Fluid mechanics includes two topics: statics and dynamics. Fluid statics treats fluids at rest while fluid dynamics treats fluids in motion. The definition of key terms in this subject area is presented in Section 3.2. 3.1.1 Fluids For the purpose of this text, a fluid may be defined as a substance that does not permanently resist distortion. An attempt to change the shape of a mass of fluid will result in layers of fluid sliding over one another until a new shape is attained. During the change in shape, shear stresses (forces parallel to a surface) will result, the magnitude of which depends upon the viscosity (to be discussed shortly) of the fluid and the rate of sliding. However, when a final shape is reached, all shear stresses will have disappeared. Thus, a fluid at equilibrium is free from shear stresses. This definition applies for both liquids and gases. 3.2 DEFINITIONS Standard key definitions, particularly as they apply to fluid flow, follow. 3.2.1 Temperature Whether in a gaseous, liquid, or solid state, all molecules possess some degree of kinetic energy; that is, they are in constant motion—vibrating, rotating, or translating. The kinetic energies of individual molecules cannot be measured, but the combined effect of these energies in a very large number of molecules can. This measurable quantity is known as temperature ; it is a macroscopic concept only and as such does not exist on the molecular level. Temperature can be measured in many ways; the most common method makes use of the expansion of mercury (usually encased inside a glass capillary tube) with increasing temperature. (However, thermocouples or thermistors are more commonly employed in industry.) The two most commonly used temperature scales are the Celsius (or Centigrade) and Fahrenheit scales...
- Amithirigala Widhanelage Jayawardena(Author)
- 2021(Publication Date)
- CRC Press(Publisher)
...These are also core subject areas taught in any civil engineering curriculum in any university. The three components of water resources engineering are fluid mechanics, hydraulics and hydrology. The objective of this book is to combine all these three core areas into a single source of reference targeted towards civil engineering students and practicing civil engineers. The contents of this book are organized into the four sub-themes: fluid mechanics, hydraulics, hydrology and water resources. This chapter begins with a brief introduction to fluid mechanics. 1.1 Fluid mechanics 1.1.1 Definition of a fluid Most materials are designated as solids, liquids or gases. Some materials have a dual designation, e.g. jellies, paints and polymer solutions (solid and fluid). All materials are deformable. Deformations of solids are small even for large external shear forces and do not continue to deform, whereas in the case of fluids, they are large even for small external shear forces and have no fixed shape. Also, in solids the strong molecular forces between molecules tend to restore the deformed body to its original state (shape) when the external force is removed. There are limits to this, i.e. within the elastic limit (Figure 1.1). Figure 1.1 (a) Deformation of a solid and a fluid; (b) deformation of a fluid and velocity profile. A fluid continuously deforms when subjected to a shear stress. It cannot sustain a shear stress when at rest, implying that shear stresses exist only when the fluid is in motion. In a real fluid (or viscous fluid), the shear stresses exist when the fluid is in motion. On the other hand, an ideal fluid (or inviscid fluid) has no shear stress when in motion. Gases and liquids are both fluids. The most significant properties that distinguish gases from liquids are the bulk modulus of elasticity and density...
eBook - ePub- B.H Brown, R.H Smallwood, D.C. Barber, P.V Lawford, D.R Hose(Authors)
- 2017(Publication Date)
- CRC Press(Publisher)
...As in structural mechanics, the aeronautical engineers have been there before us. Many of the modern computational fluid-dynamics (CFD) structures, algorithms and software were developed originally in or for the aeronautical industry. Some simplifications, such as that of inviscid flow, can lead to equations that are still worth solving for complex geometries. Special techniques have been developed, particularly for the solution of two-dimensional problems of this type. These are not discussed here because they are not particularly relevant to problems in biofluid mechanics. Turbulence is a phenomenon of primary interest to aerodynamicists, and this is reflected in the number of turbulence models that are available in commercial software and in the richness of the literature in this field. Moving boundaries (pistons and valves) are of great interest to automobile engineers in the modelling of combustion processes, and again facilities to model events featuring the motion of a boundary have existed for some time in commercial software. Of much more interest to those involved in biofluid mechanics are the problems of the interaction of soft and flexible structures with fluid flow through and around them. Historically structural and fluid-dynamic analyses have been performed by different groups of engineers and physicists, and the two communities had relatively little contact. This situation has changed dramatically in recent years. It is the authors’ belief that we stand on the verge of a revolution in our abilities to handle real problems in biofluid mechanics. 2.8.1 The differential equations For an incompressible fluid the continuity equation is ∂ u ∂ x + ∂ v ∂ y + ∂ w ∂ z = 0 where x, y and z are a set of Cartesian coordinates and u, v and w are the velocities in these three directions. The momentum equation in the x direction for a Newtonian fluid, in the absence of body forces,...
