工程流体力学英文原版Engineering Fluid Mechanics: An Introduction.Engineering fluid mechanics is a crucial discipline within the field of engineering that deals with the study of fluids and their interactions with solid boundaries. It is a fundamental branch of physics and engineering that finds applications in various fields such as civil, mechanical, aerospace, and chemical engineering. The study of fluid mechanics involves the understanding of fluid properties, fluid statics, fluid dynamics, and fluid control.1. Fluid Properties.Fluids are substances that continuously deform under the application of shear stress. They lack a fixed shape and take the shape of the container in which they are contained. Fluids can be classified as liquids or gases, depending on their state and properties. Liquids have adefinite volume but no fixed shape, while gases expand tofill the available space.Some important fluid properties include density, viscosity, compressibility, and surface tension. Density is the mass per unit volume of a fluid. Viscosity representsthe internal friction of a fluid and affects its flow behavior. Compressibility describes how a fluid responds to changes in pressure, while surface tension arises from the intermolecular forces at the fluid's surface.2. Fluid Statics.Fluid statics deals with the behavior of fluids at rest, or in equilibrium. It involves the study of pressure distribution in fluids, buoyancy, and hydrostatics.Pressure is a force per unit area acting perpendicular tothe surface, and it is a fundamental quantity in fluid mechanics. Buoyancy is the upward force exerted by a fluid on an immersed object, and it is responsible for thefloating of objects on water. Hydrostatics deals with the equilibrium of fluids under the influence of gravity andother external forces.3. Fluid Dynamics.Fluid dynamics is concerned with the motion of fluids and the forces acting on them. It involves the study of fluid flow, fluid mechanics equations, and fluid control. Fluid flow can be laminar or turbulent, depending on the velocity and other fluid properties. Laminar flow is smooth and orderly, while turbulent flow is chaotic and irregular.The fundamental equations of fluid dynamics include the conservation of mass, momentum, and energy. The conservation of mass states that the rate of change of mass within a control volume is equal to the net mass flow rate into the volume. The conservation of momentum relates the forces acting on a fluid element to its acceleration, while the conservation of energy accounts for the conversion of energy forms within a fluid system.4. Fluid Control.Fluid control involves the manipulation and manipulation of fluid flow using pumps, valves, and other devices. Pumps are used to increase the pressure or flow rate of a fluid, while valves are used to control the direction or amount of fluid flow. Other devices such as nozzles, diffusers, and turbines are also employed to modify fluid flow characteristics.In conclusion, engineering fluid mechanics is a crucial discipline that deals with the study of fluids and their interactions with solid boundaries. It involves the understanding of fluid properties, fluid statics, fluid dynamics, and fluid control. This knowledge is essentialfor engineers to design, analyze, and optimize fluid systems in various engineering applications.。
