Fluid Mechanics - Fundamentals and Applications 3rd Edition by Cengel and Applications Third Edition by Yunus A. Çengel & John M. Cimbala for free? fluid-mechanics-fundamentals-applications-3rd-edition-cengel-solutions-manual. pdf. Fluid. Mechanics. Fundamentals and. Applications, 3rd Edition by Yunus Cengel and John. Cimbala () FLUID. MECHANICS,. Cengel Cimbala Solutions. Chappdf - Download as. PDF File .pdf), Text File. Fluid mechanics: fundamentals and applications / Yunus A. Çengel, John M. Cimbala.—1st ed. edition (), and the coauthor of the textbook Fundamentals of Thermal-. Fluid .. TABLE A–3E Properties of Saturated Water TABLE .. with PDF files by chapter, all text chapters and appendices as downloadable.
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Fluid Mechanics Fundamentals and Applications 3rd Edition [Cengel and Cimbala ]. Uploaded by. Ahmad Alnajjar. Download with Google Download with. pdf. Fluid Mechanics Fundamentals and Applications 3rd ed. Pages .. PHILOSOPHY AND GOAL The Third Edition of Fluid Mechanics: Fundamentals .. Yunus A. Çengel John M. Cimbala ronaldweinland.info xxii 12/20/12 AM. Solutions Manual for. Fluid Mechanics: Fundamentals and Applications. Third Edition. Yunus A. Çengel & John M. Cimbala. McGraw-Hill, CHAPTER 1.
This is proprietary material solely for authorized instructor use. Not authorized for sale or distribution in any manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part. Analysis In the flow of a liquid, cavitation is the vaporization that may occur at locations where the pressure drops below the vapor pressure. The vapor bubbles collapse as they are swept away from the low pressure regions, generating highly destructive, extremely high-pressure waves. This phenomenon is a common cause for drop in performance and even the erosion of impeller blades. Not all cavitation is undesirable.
In this process, the water becomes saltier and denser. Once sea ice forms, salts are left out of the ice, a process known as brine exclusion.
The water across the northern Atlantic ocean becomes so dense that it begins to sink down through less salty and less dense water. The convective action is not unlike that of a lava lamp. This downdraft of heavy, cold and dense water becomes a part of the North Atlantic Deep Water , a southgoing stream. Mantle convection is the slow creeping motion of Earth's rocky mantle caused by convection currents carrying heat from the interior of the earth to the surface.
Creation accretion occurs as mantle is added to the growing edges of a plate. This hot added material cools down by conduction and convection of heat. At the consumption edges of the plate, the material has thermally contracted to become dense, and it sinks under its own weight in the process of subduction at an ocean trench.
This subducted material sinks to some depth in the Earth's interior where it is prohibited from sinking further. The subducted oceanic crust triggers volcanism. Main article: Stack effect The Stack effect or chimney effect is the movement of air into and out of buildings, chimneys, flue gas stacks, or other containers due to buoyancy.
Buoyancy occurs due to a difference in indoor-to-outdoor air density resulting from temperature and moisture differences. The greater the thermal difference and the height of the structure, the greater the buoyancy force, and thus the stack effect. The stack effect helps drive natural ventilation and infiltration.
Some cooling towers operate on this principle; similarly the solar updraft tower is a proposed device to generate electricity based on the stack effect.
Main articles: Convection zone and granule solar physics An illustration of the structure of the Sun and a red giant star, showing their convective zones. These are the granular zones in the outer layers of these stars.
Granules—the tops or upper visible sizes of convection cells, seen on the photosphere of the Sun. These are caused by the convection in the upper photosphere of the Sun. North America is superimposed on the same scale, to indicate scale. The convection zone of a star is the range of radii in which energy is transported primarily by convection. Granules on the photosphere of the Sun are the visible tops of convection cells in the photosphere, caused by convection of plasma in the photosphere.
The rising part of the granules is located in the center where the plasma is hotter. The outer edge of the granules is darker due to the cooler descending plasma. A typical granule has a diameter on the order of 1, kilometers and each lasts 8 to 20 minutes before dissipating. Below the photosphere is a layer of much larger "supergranules" up to 30, kilometers in diameter, with lifespans of up to 24 hours.
Main article: Convection oven A convection oven is an oven that has fans to circulate air around food, using the convection mechanism to cook food faster than a conventional oven. A small fan circulates the air in the cooking chamber. There are a variety of circumstances in which the forces required for natural and forced convection arise, leading to different types of convection, described below.
In broad terms, convection arises because of body forces acting within the fluid, such as gravity. The causes of convection are generally described as one of either "natural" "free" or "forced", although other mechanisms also exist discussed below. However, the distinction between natural and forced convection is particularly important for convective heat transfer. Main article: Natural convection This color schlieren image reveals thermal convection from a human hand in silhouette to the surrounding still atmosphere.
Natural convection, or free convection, occurs due to temperature differences which affect the density, and thus relative buoyancy, of the fluid. Heavier denser components will fall, while lighter less dense components rise, leading to bulk fluid movement.
Natural convection can only occur, therefore, in a gravitational field. A common example of natural convection is the rise of smoke from a fire. It can be seen in a pot of boiling water in which the hot and less-dense water on the bottom layer moves upwards in plumes, and the cool and more dense water near the top of the pot likewise sinks. Natural convection will be more likely and more rapid with a greater variation in density between the two fluids, a larger acceleration due to gravity that drives the convection or a larger distance through the convecting medium.
Natural convection will be less likely and less rapid with more rapid diffusion thereby diffusing away the thermal gradient that is causing the convection or a more viscous sticky fluid. The onset of natural convection can be determined by the Rayleigh number Ra.
Note that differences in buoyancy within a fluid can arise for reasons other than temperature variations, in which case the fluid motion is called gravitational convection see below. However, all types of buoyant convection, including natural convection, do not occur in microgravity environments.
All require the presence of an environment which experiences g-force proper acceleration. Main article: Forced convection In forced convection, also called heat advection, fluid movement results from external surface forces such as a fan or pump.
Forced convection is typically used to increase the rate of heat exchange. Many types of mixing also utilize forced convection to distribute one substance within another. Forced convection also occurs as a by-product to other processes, such as the action of a propeller in a fluid or aerodynamic heating. Fluid radiator systems, and also heating and cooling of parts of the body by blood circulation, are other familiar examples of forced convection.
Forced convection may happen by natural means, such as when the heat of a fire causes expansion of air and bulk air flow by this means. In microgravity, such flow which happens in all directions along with diffusion is the only means by which fires are able to draw in fresh oxygen to maintain themselves. The shock wave that transfers heat and mass out of explosions is also a type of forced convection.
Although forced convection from thermal gas expansion in zero-g does not fuel a fire as well as natural convection in a gravity field, some types of artificial forced convection are far more efficient than free convection, as they are not limited by natural mechanisms.
For instance, a convection oven works by forced convection, as a fan which rapidly circulates hot air forces heat into food faster than would naturally happen due to simple heating without the fan. Gravitational or buoyant convection[ edit ] Gravitational convection is a type of natural convection induced by buoyancy variations resulting from material properties other than temperature. Typically this is caused by a variable composition of the fluid.
If the varying property is a concentration gradient, it is known as solutal convection. Similarly, variable composition within the Earth's interior which has not yet achieved maximal stability and minimal energy in other words, with densest parts deepest continues to cause a fraction of the convection of fluid rock and molten metal within the Earth's interior see below.
Gravitational convection, like natural thermal convection, also requires a g-force environment in order to occur. Main article: Granular convection Vibration-induced convection occurs in powders and granulated materials in containers subject to vibration where an axis of vibration is parallel to the force of gravity.
When the container accelerates upward, the bottom of the container pushes the entire contents upward. Analysis A flowing fluid possesses flow energy, which is the energy needed to push a fluid into or out of a control volume, in addition to the forms of energy possessed by a non-flowing fluid.
The total energy of a non-flowing fluid consists of internal and potential energies. If the fluid is moving as a rigid body, but not flowing, it may also have kinetic energy e. The total energy of a flowing fluid consists of internal, kinetic, potential, and flow energies. Flow energy is not to be confused with kinetic energy, even though both are zero when the fluid is at rest. Analysis The macroscopic forms of energy are those a system possesses as a whole with respect to some outside reference frame.
The microscopic forms of energy, on the other hand, are those related to the molecular structure of a system and the degree of the molecular activity, and are independent of outside reference frames. Analysis The sum of all forms of the energy a system possesses is called total energy.
In the absence of magnetic, electrical, and surface tension effects, the total energy of a system consists of the kinetic, potential, and internal energies. Discussion a. All three constituents of total energy kinetic, potential, and internal need to be considered in an analysis of general fluid flow.
Analysis The internal energy of a system is made up of sensible, latent, chemical, and nuclear energies. The sensible internal energy is due to translational, rotational, and vibrational effects. Discussion We deal with the flow of a single phase fluid in most problems in this textbook; therefore, latent, chemical, and nuclear energies do not need to be considered.
Analysis Thermal energy is the sensible and latent forms of internal energy.
It does not include chemical or nuclear forms of energy. In common terminology, thermal energy is referred to as heat. However, like work, heat is not a property, whereas thermal energy is a property. Analysis Using specific heat values at the average temperature, the changes in the specific internal energy of ideal gases can be determined from u c v,avg T.
For incompressible substances, cp cv c and u c avg T. If the fluid can be treated as neither incompressible nor an ideal gas, property tables must be used.
Analysis Using specific heat values at the average temperature, the changes in specific enthalpy of ideal gases can be determined from h c p,avg T. For incompressible substances, cp cv c and h u vP c avg T vP. The total energy of saturated water vapor flowing in a pipe at a specified velocity and elevation is to be.
The enthalpy of the vapor at the specified temperature can be found in any thermo text to be energy is determined as. Note that only 0.
Analysis The coefficient of compressibility represents the variation of pressure of a fluid with volume or density at constant temperature. Isothermal compressibility is the inverse of the coefficient of compressibility, and it represents the fractional change in volume or density corresponding to a change in pressure. Analysis The coefficient of volume expansion represents the variation of the density of a fluid with temperature at constant pressure. It differs from the coefficient of compressibility in that the latter represents the variation of pressure of a fluid with density at constant temperature.
The coefficient of volume expansion of an ideal gas is equal to the inverse of its absolute temperature. We are to discuss the sign of the coefficient of compressibility and the coefficient of volume expansion.
Analysis The coefficient of compressibility of a fluid cannot be negative, but the coefficient of volume expansion can be negative e. Chapter 2 Properties of Fluids Solution Water at a given temperature and pressure is heated to a higher temperature at constant pressure.
The change in the density of water is to be determined. Assumptions 1 The coefficient of volume expansion is constant in the given temperature range. Analysis When differential quantities are replaced by differences and the properties and are assumed to be constant, the change in density in terms of the changes in pressure and temperature is expressed approximately as P T The change in density due to the change of temperature from 15C to 95C at constant pressure is T 0.
This is mostly due to varying with temperature almost linearly. Note that the density of water decreases while being heated, as expected. This problem can be solved more accurately using differential analysis when functional forms of properties are available.
The percent increase in density of the gas when compressed at a higher pressure is to be determined. At 10 atm: At atm:. Therefore, the percent increase in the specific volume of an ideal gas during isobaric expansion is equal to the percent increase in absolute temperature. The increase in the density of water is to be determined. Assumptions 1 The isothermal compressibility is constant in the given pressure range.
Analysis When differential quantities are replaced by differences and the properties and are assumed to be constant, the change in density in terms of the changes in pressure and temperature is expressed approximately as PT The change in density due to a change of pressure from 1 atm to atm at constant temperature is P 4.
The volume of an ideal gas is reduced by half at constant temperature. The change in pressure is to be The process is isothermal and thus the temperature remains constant. Note that at constant temperature, pressure and volume of an ideal gas are inversely proportional. The change in the density of the refrigerant is to be determined. Analysis When differential quantities are replaced by differences and the properties and are assumed to be constant, the change in density in terms of the changes in pressure and temperature is expressed approximately as P T The change in density due to the change of temperature from 10C to 0C at constant pressure is T 0.
Note that the density increases during cooling, as expected. Chapter 2 Properties of Fluids Solution A water tank completely filled with water can withstand tension caused by a volume expansion of 0.
The maximum temperature rise allowed in the tank without jeopardizing safety is to be determined. Assumptions 1 The coefficient of volume expansion is constant. Analysis When differential quantities are replaced by differences and the properties and are assumed to be constant, the change in density in terms of the changes in pressure and temperature is expressed approximately as PT A volume increase of 0.
Discussion This result is conservative since in reality the increasing pressure will tend to compress the water and increase its density.
Analysis When differential quantities are replaced by differences and the properties and are assumed to be constant, the change in density in terms of the changes in pressure and temperature is expressed approximately as PT A volume increase of 1. Then the decrease in density due to a temperature rise of T at constant pressure is 0.
The change in temperature is exactly half of that of the previous problem, as expected. Chapter 2 Properties of Fluids Solution The density of seawater at the free surface and the bulk modulus of elasticity are given. The density and pressure at a depth of m are to be determined. Assumptions 1 The temperature and the bulk modulus of elasticity of seawater is constant.
Then the density at m is estimated to be. The pressure increases required to reduce the volume of water by 1 percent and then by 2 percent are to be determined. Assumptions 1 The coefficient of compressibility is constant. Analysis a A volume decrease of 1 percent can mathematically be expressed as v V 0. Assumptions 1 There are no losses. Properties The specific heat of water is approximated as a constant, whose value is 0. In fact, c remains constant at 0. For this same temperature range, the density varies from We approximate the density as constant, whose value is For a constant pressure process, u cavg T.
Since this is energy per unit mass, we must multiply by the. Discussion We give the final answer to 3 significant digits. The actual energy required will be greater than this, due to heat transfer losses and other inefficiencies in the hot-water heating system.
Discussion The coefficient of volume expansion of an ideal gas is not constant, but rather decreases with temperature. However, for small temperature differences, is often approximated as a constant with little loss of accuracy.
The result is to be compared to ideal gas and experimental values. For the ideal gas behavior, the coefficient of compressibility is equal to the pressure Eq. Therefore we get.
Chapter 2 Properties of Fluids Solution The water contained in a piston-cylinder device is compressed isothermally. The energy needed is to be determined. Assumptions 1 The coefficient of compressibility of water remains unchanged during the compression. Analysis We take the water in the cylinder as the system. The energy needed to compress water is equal to the work done on the system, and can be expressed as. In terms of finite changes, the fractional change due to change in pressure can be expressed approximately as Eq.
Realizing that 10 kg water occupies initially a volume of the final volume of water is determined to be Then the work done on the water is. Chapter 2 Properties of Fluids Solution We are to explain how objects like razor blades and paper clips can float on water, even though they are much denser than water.
Analysis Just as some insects like water striders can be supported on water by surface tension, surface tension is the key to explaining this phenomenon. If we think of surface tension like a skin on top of the water, somewhat like a stretched piece of balloon, we can understand how something heavier than water pushes down on the surface, but the surface tension forces counteract the weight to within limits by providing an upward force.
Since soap decreases surface tension, we expect that it would be harder to float objects like this on a soapy surface; with a high enough soap concentration, in fact, we would expect that the razor blade or paper clip could not float at all. If the razor blade or paper clip is fully submerged breaking through the surface tension , it sinks. See More. No part of this Manual may be reproduced, displayed or distributed Chapter 2 Properties of Fluids in any form or by any means, electronic or otherwise, without the prior written permission of McGraw-Hill.
Discussion Mass, number of moles, and molar mass are often confused. Discussion An example of an intensive property is temperature. An example of an extensive property is mass. Discussion Specific gravity is dimensionless and unitless [it is just a number without dimensions or units].
Discussion If specific weight were an extensive property, its value for half of the system would be halved. Discussion Since molar mass has dimensions of mass per mole, R and Ru do not have the same dimensions or units. Chapter 2 Properties of Fluids Solution Assumptions The pressure in a container that is filled with air is to be determined. Properties The gas constant of air is R 0. According to the ideal gas equation of state, mRT P V 1 lbm 0.
According to the ideal gas equation of state, v Discussion RT P 0. Assumptions 1 At specified conditions, air behaves as an ideal gas. Properties The gas constant of air is R Assumptions At specified conditions, helium behaves as an ideal gas. Chapter 2 Properties of Fluids Solution A cylindrical tank contains methanol at a specified mass and volume. Assumptions 1 The volume of the tank remains constant.
Analysis An Excel sheet gives the following results. Properties The gas constant of air is Ru We are to determine if temperature increases or remains constant when the pressure of a boiling substance Analysis If the pressure of a substance increases during a boiling process, the temperature also increases since the boiling or saturation temperature of a pure substance depends on pressure and increases with it.
Properties The vapor pressure of water at 70F is 0. Properties The vapor pressure of water at 20C is 2. Properties The vapor pressure of water at 30C is 4. Discussion Flow energy is not to be confused with kinetic energy, even though both are zero when the fluid is at rest.