OPERATIONS TRAINING PROGRAM

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2 Contents:--- Table of Contents: NOTICE: If you plan to use this material in a classroom setting, then please purchase the exam bank and answer key from the Scribd store for $4.99 or visit marathonjohnb at Scribd. The exam is given at the end of the course and has specific questions for each chapter...ii Contents:---...iii Chapter 1 INTRODUCTION TO FLUIDS...12 Introduction...12 Description of Fluids...13 Humidity...14 Relative Humidity...14 Density () and Specific Volume ()...14 Density Differences for Non-Mixable (Non-Miscible) Fluids...15 Specific Gravity...18 Pressure (p)...21 Pressure Measurements...23 Absolute, Gage, and Vacuum Pressure Relations...30 Buoyancy...32 Hydrostatic Pressure...34 Pascal's Law (the law of hydraulics)...39 Pressure Difference for Fluid Flow...41 Chapter 1 Summary...43 Chapter 2 Compression of Fluids...45 Compressibility...45 The Combined Gas Law...45 Effects of Pressure Changes on Confined Fluids...47 Effects of Temperature Changes on Confined Fluids...48 Filling and Venting...48

3 Chapter 2 Summary...51 Chapter 3 NATURAL CIRCULATION FLOW...53 Natural Circulation...53 Conditions Required For Natural Circulation...54 Chapter 3 Summary...56 Chapter 4 VOLUMETRIC AND MASS FLOW RATE...57 Volume (V)...57 Volumetric Flow Rate ()...59 Mass, Density, and Specific Volume...64 Mass Flow Rate ()...66 The Steady Flow Condition...68 Continuity of Flow...68 Chapter 4 Summary...75 Chapter 5 TYPES OF FLOW...77 Laminar Flow...77 Turbulent Flow...77 Factors Influencing Type of Flow...78 Ideal Fluid...79 Noise Level and Flow Rate...79 Chapter 5 Summary...80 Chapter 6 FORMS OF ENERGY &THE GENERAL ENERGY EQUATION...81 General Energy Equation...81 Potential Energy (PE)...83 Kinetic Energy (KE)...84 Flow Energy (FE)...84 Internal Energy (U)...87 Heat, as an operator controlled input or output (Q)...88 Work, as an operator controlled input or output (W)...89 General Energy Equation...89 A Special Case of the General Energy Equation: Bernoulli's Principle...92 Simplified Bernoulli's Equation...94 Specific Energies...96 Chapter 6 Summary:...98 ENERGY CONVERSIONS IN IDEAL FLUID SYSTEMS...99

4 Energy Conversions in Ideal Fluid Systems...99 Energy Conversions for Changes in Cross-Sectional Area (Flow Area)...99 Energy Conversions for Changes in Elevation Chapter 7 Summary: Chapter 7 Energy Conversions in Real Fluid Systems Friction Fluid Friction Viscosity Energy Conversion by Fluid Friction in Real Fluids Energy Conversion by Fluid Friction Open versus Closed Fluid Flow Systems Energy Conversions in Closed Systems _Head_ Head Loss due to Friction Throttling Overcoming Head Losses Centrifugal Pump Operation Positive Displacement Pump Operation Using the General Energy Equation to Analyse Real Fluids Specific Rules Using Arrow Analysis The General Energy Equation and Diagnosis using Arrow Analysis Chapter 8 Summary: Chapter 8 Fluid Flow Measurement Flow Measuring Devices Differential Pressure Meters Orifice Plates Flow Nozzles Venturi Tubes Other Applications of the Venturi Principle Chapter 9 Summary: Water Hammer and Pipe Whip Mechanisms of Water Hammer Occurrence of Water Hammer (and Steam Hammer) Cavitation Cavitation in Centrifugal Pumps...165

5 Net Positive Suction Head (NPSH) Conditions Causing Cavitation Minimizing Gas Formation in Liquid Piping Systems Other Pump Problems Possible Results of Water Hammer Methods of Water (and Steam) Hammer/ Pipe Jet & Pipe Whip Prevention Chapter 10 Summary Chapter 9 Unintended Siphoning Introduction Siphoning Chapter 11 Summary List of Figures: Figure 1-1 Example of non-miscible fluids...15 Figure 1-2 Pressure caused by Molecules...22 Figure 1-3 Force versus Pressure...22 Figure 1-4 Pressure Scales...24 Figure 1-5 Typical Pressure Gage...24 Figure 1-6 Liquid Supported by Atmospheric Pressure...25 Figure 1-7 Buoyancy Forces on an Object...33 Figure 1-8 Relationship between Liquid Level and Pressure...34 Figure 1-9 Pressure Versus Height...35 Figure 1-10 Static Head versus Pressure...36 Figure 1-11 Head and Pressure Illustration...38 Figure 1-12 Pressurizing a...40 Figure 1-13 Hydraulic System Forces...40 Figure 1-14 A Simple Hydraulic System...41 Figure 3-15 Air Baloon Buoyancy...53 Figure 3-16 Heat Source / Heat Sink...54 Figure 4-17 Volume of an Object...57 Figure 4-18 Volume of Pipe Section A...58

6 Figure 4-19 Volume of Pipe Section B...58 Figure 4-20 Volumetric flow Rate Visual...59 Figure 4-21 Volumetric Flow rate Between Two Points...60 Figure 4-22 Volumetric Flow Rate Example Figure 4-23 Volumetric Flow Rate Example Figure 4-24 Mass Flow Rate Example...67 Figure 4-25 Continuity of Flow...68 Figure 4-26 Continuity Example Figure 5-27 The Two Basic Types of Fluid Flow...78 Figure 6-28 A Visual of Potential Energy...83 Figure 6-29 Visual of Kinetic Energy...84 Figure 6-30 Flow Energy in Compressing Piston...85 Figure 6-31 Flow Energy in Fluid Flow through a Pipe...85 Figure 6-32 Visual of Flow Energy...86 Figure 6-33 Visual of Internal Energy...87 Figure 6-34 Visual of Heat Energy...88 Figure 6-35 Visual of Work Energy...89 Figure 6-36 Fluid Energies 'IN' versus 'OUT'...90 Figure 6-37 Energies Added versus Energies Removed...90 Figure 6-38 Visual of the General Energy Equation...91 Figure 6-39 Bernoulli's Principle...92 Figure 6-40 Ping Pong Ball Floating in Air Stream...93 Figure 6-41 Air Passing Above and Below Airplane Wing...93 Figure 6-42 Air Passing by a Thrown Baseball...94 Figure 7-43 Pipe Section with a Reduction in Area Figure 7-44 Pipe Section With Increase in Area Figure 7-45 Pipe Section with Increasing Elevation Figure 7-46 Pipe Section with Decreasing Elevation Figure 8-47 Straight Pipe Section Figure 8-48 Pipe Section with Changes in size and Elevation Figure 8-49 The Pressure Drop from a 1 F Temperature Rise...111

7 Figure 8-50 Pressure Drop and Fluid Friction Figure 8-51 Energy Conversions in a Closed System Figure 8-52 A Simple Closed Loop System Figure 8-53 Closed Loop Example Figure 8-54 Pressure is Proportional to Column Height Figure 8-55 Pressures Within a Fluid Flow System (exaggerated) Figure 8-56 Total Static Head Examples Figure 8-57 Typical Valve Figure 8-58 A Centrifugal Pump Figure 8-59 Pressures Within a Centrifugal Pump Figure 8-60 Positive Displacement Pump Figure 8-61 General Energy Equation in Mental Form Figure 9-62 A Simple Orifice Plate Figure 9-63 A Simple Flow Nozzle Figure 9-64 Simple Venturi Tube Figure 9-65 Auto Carburetor Uses Venturi Principle Figure 9-66 A Typical Steam Jet Figure 9-67 A Simple Eductor Figure Case 1 Valve Quickly Closed Figure Case 2 Valve Quickly Opened Figure Case 3: Cold Condensate in Steam Line Figure Case 4: Hot Condensate in Steam Line Figure Case 5: Boiling Figure Cavitation in a Centrifugal Pump Figure Cavitation and the Collapsing Bubble Figure Pump Runout Figure Low Suction Pressure Figure Pipe Rocket / Pipe Jet Figure Pipe Whip Figure Example of a Siphon...178

8 List of Tables: Table 1-1 Densities of Common Materials...15 Table 1-2 Densities of Common Fluids...21 Table 1-3 Common Pressure Units...26 Table 1-4 Absolute, Gage and Vacuum Pressure...30 List of Terminal Objectives: TO 1.0Given the necessary fluid system parameters, SOLVE for unknown fluid parameter values as system conditions are varied...12 TO 2.0Given the necessary fluid system parameters and using the Combined Ideal Gas Law, DESCRIBE the compressibility or incompressibility of a fluid when a pressure is exerted...45 TO 3.0For any natural circulation fluid system, DESCRIBE the mechanism that allows for fluid flow...53 TO 4.0Using fluid system volumetric and mass flow rates, SOLVE for unknown fluid parameters values to predict fluid system characteristics...57 TO 5.0Given the necessary fluid system parameters, DETERMINE the fluid flow type and the flow characteristics of that fluid system...77 TO 6.0Given a fluid system, IDENTIFY the forms of energy using the General Energy Equation...81 TO 7.0GIVEN an Ideal fluid system where no heat is transferred in or out, and no work is performed on or by the fluid, EXPLAIN the energy conversions that occur...99 TO 8.0GIVEN a Real fluid system, DESCRIBE the effects of fluid friction to predict energy conversions TO 9.0EXPLAIN the energy conversions that occur as fluid flows through the Venturi tube, flow nozzle, and orifice plate flow measuring devices TO 10.0IDENTIFY the conditions and prevention methods for both "water hammer" and "pipe whip" in fluid systems TO 11.0IDENTIFY the conditions and prevention methods of a fluid siphon for a fluid system...177

9 References: ARITHMETIC: Student Text, TTFGMAPA.H0102, rev. 2 / Westinghouse Savannah River Company, Aiken, SC MATHEMATICS: Student Text, TTFGMA1A.H0104, rev. 4 / Westinghouse Savannah River Company, Aiken, SC Bay, Denise and Horton, Robert B., Macmillan Physical Science, Teacher's Edition, Macmillan Publishing Co., New York, (1988). Cline, John W., Thermodynamics, Heat Transfer, and Fluid Flow, Westinghouse Savannah River Company HLW Fundamentals Training Program, (1993). Driskell, Les., Control Valve Selection and Sizing, Instrument Society of America, North Carolina, (1983). Driskell, Les, Control-Valve Selection and Sizing, Independent Learning Module, Instrument Society of America, Publishers Creative Services Inc., Research Triangle Park, North Carolina, (1983). Durham, Franklin P., Thermodynamics, 2nd ed., Prentice-Hall, Inc., New Jersey, (1959). Freeman, Ira M., Physics Made Simple, Revised Edition, Bantan Doubleday Dell Publishing Group, Inc., New York, (1990). Giancoli, Douglas C., Physics, 3rd ed, Prentice Hall, New Jersey, (1991). Glasstone, Samuel and Sesonske, Alexander, Nuclear Reactor Engineering, 3rd ed., Van Nostrand Reinhold Co., New York, (1981). Heimler, Charles H. and Price, Jack S., Focus on Physical Science, Teacher's Edition, Charles E. Merrill Publishing Co., Ohio (1984). Hewitt, Paul G., Conceptual Physics...a new introduction to your environment, 3rd ed., Little Brown and Company, Inc., Boston, (1977). Holman, J. P., Thermodynamics, 4th ed., McGraw Hill, Inc., New York, (1988). Julty, Sam, How Your Car Works, Book Division, Times Mirror Magazines, Inc., New York (1974). Murphy, James T., Zizewitz, Paul W., and Hollon, James Max, Physics Principles & Problems, Charles E. Merrill Publishing Co., Ohio, (1986). Serway, Raymond A. and Faughn, Jerry S., College Physics, 2nd ed., Saunders College Publishing, Philadelphia, (1989). U.S. Department of Energy, DOE Fundamentals Handbook, Thermodynamics, Heat Transfer, and Fluid Flow, Vols. 1 through 3, U.S. Department of Energy, (1992). Wiedner, Richard T. and Sells, Robert L., Elementary Classical Physics, College Physics Series, Vol. 1, Allyn and Bacon, Inc, Boston, (1965).

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11 Student Guide: Fluid Flow OPERATIONS TRAINING PROGRAM Chapter 1: Introduction to Fluids Chapter 1 INTRODUCTION TO FLUIDS This chapter introduces various terms used to describe the characteristics of a fluid and some basic flow characteristics of given fluids in a typical application. It also presents the relationship between various parameters within a given fluid system under various conditions TO 1.0 EO 1.1 EO 1.2 EO 1.3 EO 1.4 EO 1.5 EO 1.6 EO 1.7 EO 1.8 EO 1.9 Given the necessary fluid system parameters, SOLVE for unknown fluid parameter values as system conditions are varied DEFINE the following Fluid Flow terms to include their typical units: specific volume, density, and specific gravity EXPLAIN what will occur when two non-mixable fluids are placed in the same container CALCULATE a fluid s density, specific volume, or specific gravity when given any one of the other quantities DEFINE the Fluid Flow term Pressure to include units Given the necessary fluid parameters, CALCULATE/CONVERT absolute pressure, gage pressure, feet of head, or vacuum pressure for a fluid system EXPLAIN Archimede s Principle and relate it to the term Buoyancy DESCRIBE the relationship between the pressure in a fluid column and the density and depth of the fluid DEFINE the Fluid Flow term Head to include units EXPLAIN the concept of Pascal s law, including its applications. Introduction Fluid flow is an important part of most industrial processes; especially those involving the transfer of heat. Frequently, when it is desired to remove heat from the point at which it is generated, some type of fluid is involved in the heat transfer process. Examples of this are the cooling water circulated through a gasoline or diesel engine, the air flow past the windings of a motor, and the flow of water through the core of a nuclear reactor. Fluid flow systems are also commonly used to provide lubrication. Fluid flow in the nuclear field can be complex and is not always subject to rigorous mathematical analysis. Unlike solids, the particles of fluids move through piping and components at different velocities and are often subjected to different accelerations.

12 Student Guide: Fluid Flow OPERATIONS TRAINING PROGRAM Chapter 1: Introduction to Fluids Even though a detailed analysis of fluid flow can be extremely difficult, the basic concepts involved in fluid flow problems are fairly straightforward. These basic concepts can be applied in solving fluid flow problems through the use of simplifying assumptions and average values, where appropriate. Even though this type of analysis would not be sufficient in the engineering design of systems, it is very useful in understanding the operation of systems and predicting the approximate response of fluid systems to changes in operating parameters. The basic principles of fluid flow include three concepts or principles; the first two of which the student has been exposed to in previous manuals. The first is the principle of momentum (leading to equations of fluid forces) which was covered in the manual on Classical Physics. The second is the conservation of energy (leading to the First Law of Thermodynamics) which was studied in thermodynamics (Heat Transfer). The third is the conservation of mass (leading to the continuity equation) which will be explained in this module. Description of Fluids A fluid is any substance that flows. The molecules of fluids are not rigidly attached to each other. Essentially, fluids are materials which have no repeating crystalline structure. Fluids include both liquids and gases. Liquids are fluids which have a definite volume and take the shape of their container. Gases also take the shape of their container; however, they will expand to completely fill the container thus they do not have a definite volume. Several properties of fluids are discussed in the Heat Transfer course. These include temperature, pressure, mass, specific volume and density. Temperature is defined as the relative measure of how hot or cold a material is. It can be used to predict the direction that heat will be transferred. Pressure is defined as the force per unit area. Common units for pressure are pounds force per square inch (psi). Mass is defined as the quantity of matter contained in a body and is to be distinguished from weight, which is measured by the pull of gravity on a body. The specific volume of a substance is the volume per unit mass of the substance. Typical units are ft 3 /lbm. Density, on the other hand, is the mass of a substance per unit volume. Typical units are lbm/ ft 3 Density and specific volume are the inverse of one another. Both density and specific volume are dependant on the temperature and somewhat on the pressure of the fluid. As the temperature of the fluid increases, the density decreases, and the specific volume increases. Since liquids are considered incompressible, an increase in pressure will result in no change in density or specific volume of the liquid. In actuality, liquids can be slightly compressed at high pressures, resulting in a slight increase in density and a slight decrease in specific volume of the liquid.

13 Student Guide: Fluid Flow OPERATIONS TRAINING PROGRAM Chapter 1: Introduction to Fluids Humidity Humidity is the amount of liquid vapor suspended in a gas (or the amount of water in air). The units of humidity are grains per cubic foot. (A grain is the weight of a wheat seed.) Relative Humidity Relative humidity is the percentage of liquid that a gas contains compared to being 100% saturated, (where it can hold no additional liquid). Units are percent. Relative humidity is a percentage measurement of humidity up to and including saturation at 100% at any particular temperature. Since air holds more water when it is at a higher temperature, air that is saturated and then heated will have the capacity to hold more water and will no longer be termed "saturated". The relative humidity of air will then be less than 100% if it's temperature is increased. As a result, without changing the amount of liquid suspended within a gas, and by only changing the temperature, the relative humidity can vary from saturated at 100% relative humidity to something considerably less than saturated. A gas can not contain more than 100% of its liquid holding capacity. If the temperature of a 100% saturated gas is decreased then its capacity to hold moisture decreases and the liquid precipitates. This is why dew accumulates on leaves and grass when the temperature goes down in the early morning hours. Density ( ρ ) and Specific Volume (υ ) Density, ρ, is the amount of mass contained in one cubic foot of space; units are mass per unit Volume. Specific volume, υ, is the amount of space occupied by one pound mass (the force of one pound converted to mass by dividing by g c ); units are Volume per unit mass. Specific volume is the inverse of density; υ = 1 ρ & ρ = 1 υ. Where: ρ = Density (Greek letter rho), lbm/ft 3 or kg/m 3, etc. m = mass, lbm or kg, etc. V = Volume, ft 3 or m 3, etc. υ = Specific volume, ft 3 /lbm or m 3 /kg, etc. Both density and specific volume measure the same property: how close the molecules or atoms of a substance are to each other. Volume (V) is the amount of space occupied by a three-dimensional figure. Volume is represented by length units cubed

14 Student Guide: Fluid Flow OPERATIONS TRAINING PROGRAM Chapter 1: Introduction to Fluids ( ft 3, in 3, m 3, etc.). The specific volume is the amount of space occupied by a unit of mass. Specific volume is the total volume V divided by the total mass m of an object. υ = V m Where: υ = specific volume, ft 3 /lbm V = volume, ft 3 m = mass, lbm A low value of density (or high value of specific volume) means the molecules or atoms in the substance are relatively far apart. This is true of gases (hydrogen, oxygen) and for vapors such as steam. Conversely, a high value of density (or low value of specific volume) means that the molecules or atoms are relatively close together. This is true of liquids (such as water) and solids such as ice. The density of a material will govern the way it behaves when put in contact with other materials. Table 1-1 lists the densities of some common materials. If a material that is very dense is placed into a container containing a less-dense liquid, the material will sink. For example, if a piece of iron is placed into a container of water, the iron will sink because it is more dense than water. If, however, that same piece of iron is placed in a liquid that is more dense, such as mercury, the iron will float. Even though iron is relatively dense, it is not as dense as the mercury. Densities of Some Common Materials: Material Density, g/cm 3 hydrogen 9.0 x 10-5 helium 2 x 10-4 air 1.3 x 10-3 Styrofoam 0.1 wood 0.7 alcohol 0.8 ice 0.92 water 1.0 sea water 1.03 aluminum 2.7 rock 3 iron 7 mercury 13.6 Density Differences for Non-Mixable (Non-Miscible) Fluids Table 1-1 Densities of Common Materials Miscibility is the property of two substances, which makes them "mixable". Salt and water are miscible so when they are mixed together they make salt water and stay mixed until separated by evaporation. But when Figure 1-1 Example of non-miscible fluids

15 Student Guide: Fluid Flow OPERATIONS TRAINING PROGRAM Chapter 1: Introduction to Fluids two substances are non-miscible (not mixable), like oil and water, the water, being the highest density liquid sinks to the bottom of the container, and the oil being less dense rises to the top. They "unmix" themselves very quickly. Oil and vinegar salad dressing is an example of this. Why do some fluids "unmix" themselves? Vinegar is more dense than olive oil; therefore, under the attraction of gravity the vinegar moves to the bottom of the container. The object with greater mass creates a greater pressure around itself than an object with a smaller mass. As a result, the lighter objects get pushed out of the way. This pressure then forces the lighter oil molecules out of the lowest regions and upward where the pressure is lower. A layering effect is created in a salad dressing bottle where the denser vinegar, under the influence of earth s gravitation, occupies the bottom of a container while the less dense olive oil is forced to rest on top. Some gases do not mix well with other gases. As an example, certain subterranean bunkers that contained poisonous chlorine gas used during the Second World War is still a potential health hazard for Europeans. Chlorine gas is a nerve agent and is heavier than air so it tends to pool in the lowest areas. It does not deteriorate nor dissipate, so it remains active, ready to permanently destroy the nervous system of anyone who may step into it. In this example it is good for one to know his or her density fundamentals. In industries today, there are an abundance of chemicals in fluid form (liquid or gas) that can be equally as dangerous to their surrounding areas. Like chlorine gas, phosgene gas and carbon monoxide are also heavier than air. Phosgene gas both suffocates and creates hydrochloric acid in the lungs. It is created in many industrial processes where foods may rot, or even where an animal decomposes near a confined space. It has the odor of new mown hay or green corn. Phosgene gas has killed and caused pneumonia in workers who entered unventilated confined spaces without wearing self contained breathing devices. Carbon monoxide exits from the exhaust pipe of a vehicle and migrates downward into confined spaces where it displaces the air. It suffocates a victim by displacing the oxygen in red blood cells. Radioactive tritium gas is a heavy form of hydrogen gas (an isotope). Tritium is many times lighter than air so it escapes upward when released. Gas bubbles of tritium in air act like bubbles of air rising from the bottom of a fish tank. This light gas rises to occupy a thin layer in the highest regions of the gas envelope that covers the earth. A comparison of the densities of two (non-mixable) items will allow us to predict which item will float and which will sink. Consider the following examples:

16 GATE Study Material Fluid Flow Operation (chemical Engineering) 84% OFF Publisher : Faculty Notes Author : Panel Of Experts Type the URL : Get this ebook